How Villainous Are the Villainous Options?

 In the primordial days of D&D, it was imagined as a game about amoral dungeon-crawling, where the Gold you hauled out of those ancient castles, deep caverns, and abandoned temples literally was the XP you earned to level up. Alignment initially focused more on the law/chaos axis, but the game worked out just fine with evil party members because ideology and morals could take a backseat to survival within a hostile environment like a dungeon.

As the game has evolved, and the influence of fantasy stories with more traditionally heroic protagonists became stronger (surely the popularity of the Lord of the Rings movies in the early 2000s, where its heroes are on their adventure purely to save the world, was a part of that,) I think it has been trickier to have truly villainous PCs. Adventures are usually about stopping some monstrous villain.

To be sure, a villainous protagonist could find themselves opposed to a villainous antagonist (consider the seasons-long arc in Breaking Bad where Walter White contends with Gus Fring, the irony being that Gus, while monstrous in his own ways, is probably not quite as evil as the show's main character).

Despite the meaning of the words (protagonist is the instigator of the "agony" of the dramatic story,) which originate in Greek tragedies (such as Oedipus killing his father and unwittingly sleeping with his mother, and thus bringing ruin upon himself) modern storytelling, especially in genre fiction, typically has heroes reacting to some nefarious plot. Luke Skywalker might want to go out into the world and be a hero, but the specific opportunity he gets to do that is a response to the Empire killing his adoptive parents to cover up their pursuit of the documented weaknesses in their new doomsday weapon. Luke is reacting to the Empire's newest overreach, rather than setting out with a specific goal that then gets interfered with by an antagonist.

There's an argument to be made, thus, that a lot of modern heroes are actually heroic antagonists to a villain protagonist.

I bring this up because of how adventure design probably needs to work with evil-aligned PCs.

If you are doing a heroic campaign, you can still have evil party members. Neither evil nor good are monoliths (in the former case, there's a major part of D&D lore, the Blood War, that makes that clear). Just because a tyrannical red dragon is burning towns in the area, the fact that they're causing suffering doesn't mean that your aspiring crime-lord Rogue won't have beef with them. Hell, even if you're an aspiring Lich (something that you can do with the Path of the Lich feats) you might really object to that dragon burning so many bodies that could have been perfectly serviceable zombie minions.

One example of this I really like is Spike in season two of Buffy the Vampire Slayer. When Buffy's vampire boyfriend Angel loses the curse that restored his soul, Angel undertakes a maniacal plot to unleash a demon that will swallow up the entire world. Spike, still a soulless vampire, decides to help Buffy stop him - not out of any benevolent intention, but because he likes that the world exists with all these humans walking around full of blood for him to drink. Sure, an apocalyptic cataclysm would be a great feat of evil, but Spike isn't into evil just for the sake of it.

One of the things I really like to think a lot about alignment is that there's the "capital" versus "lower-case" versions of each extreme of the chart (as well as Neutrality). "Capital E" Evil is someone who pursues evil ideologically, wanting to maximize suffering and pain as much as possible. "Lowercase E" Evil is someone who pursues their own interests, and is fully willing to do evil acts to get what they want, not because they want to be evil, but just because they don't really care if others get hurt.

You can apply this to everything else: Capital C Chaotic would be someone who actively wants to tear down systems and institutions, while Lowercase C Chaotic might be someone who just kind of wants to live outside of them.

Lowercase E evil characters are usually going to be less evil than Capital E evil characters (though not strictly - a somewhat impotent goblin serial killer who dreams of ruining the world but doesn't have the means to do so might be dedicated to evil but be less harmful than a callous noble who readily starts wars to distract from domestic unrest). But I also think it's going to be far easier to fit a Lowercase E evil character into a party of adventurers.

But what about our specific options?

5E already has a fair number of "dark"-themed class options. Shadow Monks, Aberrant Sorcery, most Warlock patrons - there are plenty of options for characters that could come off as quite villainous.

Looking at the recent UA, the theming of the subclasses leans toward the villainous, but I'm not sure that any of the subclasses really force you into an evil space.

Pestilence Domain, admittedly, forces you to justify worshipping a god of disease. I did mention in my breakdown of that subclass that, actually, you could argue that God in Exodus acts in a Pestilence aspect, afflicting the Egyptians with the Ten Plagues (many are more invasive species, but you've got the Boils there and arguably the death of the firstborns). I think you could also argue a Pestilence God as simultaneously being a god of medicine, evoking Paracelsus' "dosage makes the poison" and how a deity might inflict and cure diseases.

Circle of the Titan is, I think, the least obviously villainous, because the most iconic of the Titans, the Tarrasque, is actually a morally neutral figure. Sure, Krakens and Blobs of Annihilation are evil-aligned, but I can very easily see a Druid who follows this path out of a respect for the majesty of these beings that doesn't really depend on beneficence or malice.

Hell Knight Fighters do start to get into that truly morally questionable side of things: one can presume that the Infernal Wounds you inflict are particularly painful, and you might slay a foe and send their soul to the Nine Hells to become a Lemure, which is pretty unambiguously a bad thing to do (though I guess you could argue that if you kill an evil person, they're going to wind up as a Lemure, Manes, or Larva anyway).

Demonic Sorcery is, of course, tied to the chaotic evil of the Abyss, but Sorcerers usually get their powers through means outside of their control, and so it's hard to blame them for what kind of powers they get.

On a mechanical level, the Path of the Death Knight is actually somewhat neutral - it gives you some admittedly dark-themed spells and makes you undead by the end of it, but none of its spells are anything a good-aligned character couldn't get. The Hellfire Orb, sure, is unique, but again, it's nothing that someone couldn't do with a Fireball and Circle of Death. Flavor-wise, a Death Knight has to have turned their back on goodness in some way, and will remain a death knight until they atone. But I honestly think that that lore, while cool, could be expanded to include the status extending to someone who is cursed rather than choosing this path.

The Path of the Lich, though, really leans into consuming souls. I realize that there are different interpretations of what a soul literally is, but I tend to define it as the consciousness of a sentient being, and so the destruction of a soul is worse than killing someone, and maybe is the most unforgivable evil act because it robs them of any future and afterlife. While the UA post does point out the occasional good-aligned Lich, it's hard to imagine ever using Soul Siphon (a feature that most other feats interact with) and still consider yourself good. (I do have a prominent Lich NPC in my homebrew setting that I think is either Lawful Neutral or even Lawful Good, and I don't know if he just doesn't need to consume souls or if he has a system by which criminals condemned for execution who would prefer oblivion over going to the Lower Planes in the afterlife can volunteer to feed his Soul Jar. Alternatively, I might interpret a soul's "consumption" as merely being trapped in the phylactery rather than destroyed, and that if you destroy it, it frees all the Lich's victims).

I do think, ultimately, that any of these options could probably work for antiheroes or at least lowercase E evil characters. The key is that you should really coordinate with fellow players and your DM if you want to play an evil character and make sure there are clear boundaries on how that evil is expressed - what kind of in-world behavior is rich characterization and what is just going to derail the narrative.

UA: Path of the Lich

 The Lich is probably the most enduring contribution to pop culture that D&D has made. While there were characters who embodied the undead wizard in older fiction, like Thulsa Doom in the Conan books (which was kind of combined with another character for the James Earl Jones character in the movie) to evil overlords who would endlessly come back if a magical artifact was kept intact (like Sauron with his ring and Khoschei the Deathless's egg) D&D codified this type of character and gave it an enduring name: Lich, and archaic English word just meaning "body," but which now has a kind of elemental association with dark, evil, and extreme power.

And with these feats, you, too, can become one those enduring undead masters of the arcane.

Like the Path of the Death Knight, you'll begin with an Initiate feat, the prerequisites for all the other feats. Then, you'll have to pick up at least one other intermediary feat before getting the capstone Lich Ascension feat.

Liches are, in most settings, always evil (same for Death Knights) but there are some potential, maybe, paths in which you could become a more benevolent Lich. These are "villainous options" though. In the grey blurb, they do mention that liches can vary in alignments and motivations. Oddly, though, I think that the general lore is that death knights cease to be death knights if they atone, while a Lich's transformation is not really based on their moral outlook but on the steps they have taken - it's just that those steps tend to involve consuming others' souls, which is pretty evil basically any way  you look at it.

Still, I'd actually be somewhat more open to the idea of a non-evil Lich who just uses very obscure and esoteric necromantic rites that might not involved condemning anyone to oblivion.

But let's get into the feats.

Lich Initiate:

Prerequisites: Level 4+, Spellcasting or Pact Magic feature.

Ability Score Increase: Increase your Intelligence, Wisdom, or Charisma by 1, up to 20.

Creating Your Spirit Jar: Choose a tiny object of great significance to you (or roll on a table). You spend a long rest anchoring your soul to the object, allowing you to consume the souls of the living to bolster your power. You can only have one spirit jar at a time and the old one is destroyed if you create a second one.

Spirit Jar Destruction: Your spirit jar's AC is equal to your spell save DC, and it has a number of HP equal to your spellcasting ability modifier plus your character level. If the jar is destroyed, you gain 2 Exhaustion levels and you can't use the Soul Siphon ability until you create a new one.

Soul Siphon: When you reduce a Humanoid enemy to 0 Hit Points, you can consume its soul and gain a boost of arcane energy (no action required). On your next turn, the first creature you hit with an attack takes extra Necrotic damage equal to 1d6 plus your spellcasting ability modifier. You also gain this benefit if someone else reduces a Humanoid enemy within 10 feet of you to 0 HP. A soul consumed this way can be restored only by a True Resurrection or Wish spell.

    Like the Lich you are trying to become, I don't think you need the Spirit Jar to be anywhere near you. Indeed, it might best to lock it away in some secure and/or remote place. Soul Siphon is pretty powerful given that there's no limit on use, but it also only works on Humanoids.

    It's also... yeah, not really easy to imagine that flavored as anything other than evil. Note also that the boost is only to attacks, so if you're relying on saving throw spells for your damage this will not come into play a lot. Still, melee Bards, Warlocks with Eldritch Blast or Pact of the Blade, Sorcerers with Sorcerous Burst, or just a good old Fire Bolt can all benefit.

Arcane Restoration:

Prerequisite: Lich Initiate Feat

Ability Score Increase: Intelligence, Wisdom, or Charisma by 1, up to 20.

Essence Rejuvenation: When you use Soul Siphon to consume a soul, you can choose one or more expended spell slots to recover. The spell slots can have a combine level equal to no more than 4. Once you use this feature, you can't again until you finish a Short or Long rest.

    Again, you're limited to humanoids to harvest souls, but frankly, dang. Indeed, while we're probably imagining full casters using this, an Artificer, Ranger, or Paladin could also follow this path and that four levels-worth of spells looks amazing to someone who might only have 2nd level spells at this point. And that's per short rest, not just long.

    What this doesn't work well for is Warlocks, who won't have any spell slots lower than 5 a level after they pick up this feat.

Transfer Life:

Prerequisite: Lich Initiate Feat

Ability Score Increase: Intelligence, Wisdom, or Charisma by 1, up to 20 (unlike the Death Knight ones, these seem universal, which honestly makes sense).

Soul Transference: When you use Siphon Soul to consume a soul, you can choose a creature within 60 feet of yourself to gain Temp HP equal to your proficiency bonus plus your spellcasting ability modifier (minimum 1).

    We'll need to be at least level 8 (actually, I suppose an Eldritch Knight could get this at 6 in theory) so we're talking a +3 PB and probably a +4 to our spellcasting ability for this, so that 7 Temp HP. It's no action required, but maybe not stupendous.

Undead Grasp:

Prerequisite: Lich Initiate Feat

Ability Score Increase: Intelligence, Wisdom, or Charisma by 1 up to 20.

Paralyzing Touch: You know the Chill Touch cantrip, or if you already know it, you gain another cantrip of your choice. You choose Intelligence, Wisdom, or Charisma as your spellcasting ability for this when you pick this feat.

When you deal damage with Chill Touch, you can expend a level 1+ spell slot to attempt to paralyze the target. The target takes an extra 1d10 Necrotic damage per level of the spell slot consumed, and must succeed on a Con save against your spells ave DC or have the Paralyzed condition until the start of your next turn.

    On one hand, I like how this echoes the classic Lich ability. But there are a couple problems: First is that it's both an attack and a save, so they have two chances to avoid it (though in fairness, we choose to use this after we hit - it's just are we likely to actually try casting this and getting into melee range if we aren't going to use this?) The other is that the condition ends before we get to do anything to them on our next turn.

    I do think this works really well for Bladesinger Wizards, Valor Bards, and maybe Eldritch Knight Fighters, who all get to use a cantrip as the first attack in their multiattack. Paralyzing a foe and then hitting them with a weapon means an automatic crit. Great for Gishes, less great for true pure spellcasters.

Lich Ascension:

Prerequisite: Level 12+, at least two Path of the Lich feats.

Ability Score Increase: Intelligence, Wisdom, or Charisma by 1, up to 20.

Undead: Your creature type is Undead.

Unholy Anatomy: You have resistance to Necrotic and Poison damage, and you don't gain exhaustion levels from dehydration, malnutrition, or suffocation.

Frightening Gaze: You learn the Fear spell if you don't already know it and you always have it prepared. You choose Intelligence, Wisdom, or Charisma as your spellcasting ability for it when you choose the feat. You can cast the spell without expending a spell slot a number of itmes equal to your spellcasting ability modifier (minimum once) per long rest.

Rejuvenation: If you die and you have a Spirit Jar and you are not revived beforehand, you re-form in 1d10 days in the nearest unoccupied space within 5 feet of your spirit jar with all your Hit Points.

    I mean, the Rejuvenation thing is the main event for a Lich. And the only case in which I think it could be a downside is if your party needs to secure a resurrection diamond and you wind up rejuvenating before they can revive you, potentially separating you from them far away, even on another plane.

    Fear is a good spell, and this gives you several free uses of it.

    As I mentioned in the Death Knight post, being Undead has its downsides, even if healing spells now work on you just fine. And the damage resistances are good.

Overall Thoughts:

    I don't know that I love this as much as the Death Knight one - I guess that that supplemented you with a lot of extra spells because your character might not even have been a spellcaster. Most of the Lich's features focus on Soul Siphon, which, aside from the morality of it (again, this is a Villainous option) might also wind up being unusable in a campaign with little to no humanoid enemies. That's honestly a pretty big liability for something that is the crux of this character-defining feat path.

    And especially in 5.5, where lots of classic humanoid foes like Goblins or Gnolls are now classified as other creature types, it's going to be a serious problem.

    The Lich Initiate feat is actually more of a liability than a benefit if you can't use Soul Siphon, as your Spirit Jar's destruction imposes a pretty major downside.

    So, how would I build a Lich character?

Basically any spellcaster could work fairly well for this, and there are sort of too many to choose from. To go the classic route, you could go with a Necromancer Wizard (which we should be getting the 5.5 version of later this year). Naturally, we'd have to pick up Lich Initiate early on - for sake of argument, I'll say 4, though we could delay the whole progression and grab War Caster first and then take Initiate at 8 and Ascension at 16. So, what's our in-between feat?

Honestly, because of the issues raised here, I might go with Undead Grasp just to avoid putting all my eggs into the Soul Siphon basket. This will work on any foe (that isn't both immune to necrotic damage and also the paralyzed condition) so it's pretty campaign-agnostic. Arcane Restoration is very tempting, but I think I might want something like War Caster instead for my general spellcasting purposes.

It might be fun to use this on a half-caster, but because the feats only boost mental stats, the Artificer is probably the best choice in this case. Here, Arcane Restoration is going to be give us, proportionately, a pretty huge chunk of our spell slots back. The upcoming Reanimator subclass is the best thematic fit here, of course.

While we can siphon souls from any distance if we strike the killing blow, we might want to play a more close-range character to benefit from our party killing foes near us, which might make a hardier Cleric or Druid (or maybe Bard) a solid option. Again, I think a Bladesinger Wizard actually works really well for this.

    If I had any feedback (which I will for the survey that comes out next week) I'd say that the reliance on Soul Siphon, while flavorful, is very limiting to this Path, and I'd try to diversify the means by which an ascendant Lich does their business. Also, given that they explicitly call out non-evil Liches, it'd be nice to have the Lich Initiate feat use something other than this invariably heinous act. Perhaps the Soul Jar initially just increases our ability to recover HP before it fully brings us back to life, or maybe we get some other offensive ability that isn't restricted to humanoid targets and maybe doesn't have to consume souls?

I write that realizing that I don't want to de-fang this most iconic of evil monsters, and so it might be a mistake to give them the soft-focus treatment. But again, beyond the morality of Soul Siphon, the worry I have is that a player feels trapped by this set of options if they're in a campaign without a lot of humanoid foes (something that becomes almost necessary at high levels, when humanoids are just not tough enough to challenge a party).

And with that, we come to the end of this latest UA. I think there's certainly some reworking and tuning up that these options will need, but I applaud WotC thinking outside the box and giving us some truly new and innovative options.

Note that none of these four subclasses has ever appeared in any previous 5E content (one could argue the Hell Knight is thematically linked to MCDM's Illrigger, but I don't think that counts). With so much stuff getting reprinted for 5.5, which was meant to be backwards compatible (and to a large degree is,) I'm really happy to have a UA with absolutely nothing that we've seen before. So, major points for that.

UA: Path of the Death Knight

 This isn't a subclass. It's a group of associated feats that allow you to become a Death Knight. We'll see this as well as the Path of the Lich.

Conceptually, this is really cool. Let's see how it works out.

First off, there's a table for "Death Knight Journeys" to explain why your character is pursuing this path. There are classic acts of dishonor and depravity, but there are some with a bit of wiggle-room that allow you to be a more sympathetic character.

You'll need to take the Death Knight Initiate feat first, and then you'll need at least one other Death Knight feats before getting the final Death Knight Ascension feat, which requires level 12 (so no, Fighters cannot get this at level 8).

The feats' ability score bonuses clearly point toward Paladins as the most likely class to take this path, though Fighters and Barbarians can also do pretty well with them.

Also note that because you'll be taking at least three general feats to get the final one, Paladins actually might not be able to get as high Strength or Charisma as they'd like (weirdly making this possibly better on a Fighter).

Death Knight Initiate

Prerequisites: Level 4+, Weapon Mastery Feature

Ability Score Increase: Increase Strength or Charisma by 1, to a maximum of 20.

Death Points: You have a number of Death Points equal to your PB. You regain all expended Death Points when you finish a long rest.

Dread Strike: You always have Wrathful Smite prepared, using Charisma as your spellcasting ability. You can cast it without expending a spell slot by expending 1 Death Point. When you expend Death Points to cast Wrathful Smite, the target has disadvantage on the wisdom saving throws to avoid or end the spell's effects. (You can also cast the spell using spell slots, as normal, but without this bonus effect).

    Wrathful Smite is a somewhat lower-damage smite spell, but if the fear effect goes off, it's pretty useful. And at level 4, two free Wrathful Smites are pretty nice to have. (Note, here, I think Barbarians cannot cast any spells while raging, so this really does seem built for Fighters and Paladins, and I guess in theory Strength-based Rangers).

    This is the baseline feat that you need for all the others. Frightened is a good condition that admittedly a fair number of foes are immune to, but you get to pick when to use it. Let's see the subsequent ones:

Dread Authority:

Prerequisite: Death Knight Initiate Feat

Ability Score Increase: Increase Constitution or Charisma by 1, up to 20.

Dread Command: You always have Command prepared, with Charisma as you spellcasitng ability. You can cast the spell without expending a spell slot by expending 1 Death Point (or you can use a spell slot as normal). If cast with a Death Point, undead targets have disadvantage on the saving throw against the spell.

    This is interesting: we can't boost Strength with this one, but if you figure we start ourselves off with a 17 in Strength, we might get to a +4 with the first feat and then boost our Charisma next. (We don't have to take this feat, mind you).

    Command is a solid spell, one with a Charm-like effect that doesn't actually charm the target, and thus means it works on just about any creatures. It's not the most powerful, but again, we're getting a couple uses per day.

Harbinger of Doom:

Prerequisite: Death Knight Initiate Feat

Ability Score Improvement: Increase your Strength, Constition, or Charisma by 1, up to 20.

Ill Omen: You always have Bane prepared, Charisma as your spellcasting ability. You can cast it without expending a spell slot by expending 1 Death Point. When you cast it with a Death Point, affected targets subtract 1d6 instead of 1d4 from their attack rolls and saving throws.

    The ability scores here are very flexible. Bane's a fine spell, and I like the pattern of making the spells slightly better when cast with Death Points. I do wonder why we can't upcast them by spending more, though.

Deathly Presence:

Prerequisites: Level 8+, Death Knight Initiate Feat

Ability Score Improvement: Increase Strength, Constitution, or Charisma by 1, up to 20.

Awful Presence: You always have the Fear spell prepared (Charisma as spellcasting ability, you know the drill at this point). You can cast it without expending a spell slot by expending 1 Death Point. When you expend Death Points to cast Fear, you deal 2d6 psychic damage to each creature that fails its saving throw in addition to its regular effects.

    Notably, this lets us cast a 3rd level spell for just one Death Point, and it also gives us that spell a level before a Paladin typically gets 3rd level spells (and five levels before an Eldritch Knight Fighter could). Fear is a very good crowd-control spell, and by level 8, we can use it three times a day. At 9, we can cast it four times and then also spend spell slots to cast it even more.

Unholy Steed:

Prerequisites: Level 8+, Death Knight Initiate Feat

Ability Score Increase: Increases Strength or Constitution by 1, up to 20.

Spectral Steed: You always have Find Steed prepared. You can cast it without expending a spell slot by spending 1 Death Point. When you use it this way, the steed is a Fiend and targets you choose have Disadvantage on the Wisdom saving throw against Fell Glare.

    On a Fighter this is really cool. On a Paladin, this is mostly worthless, as we get Find Steed automatically and can cast it for free once per day anyway. The Otherworldly Steed bonus actions are only once per day. I'd skip this on a Paladin for sure, and honestly probably would on a Fighter as well.

Death Knight Ascension:

Prerequisites: Level 12+, two Path of the Death Knight feats

Ability Score Increase: Increase your Strength or Charisma by 1, to a maxium of 20.

Undead: Your creature type is Undead.

Unholy Anatomy: You have resistance to Necrotic and Poison damage. You don't gain exhaustion from dehydration, malnutrition, or suffocation.

Hellfire Orb: As a magic action, you can expend 1 to 5 Death Points to throw an orb of hellfire at a point within 120 feet. Each creatuer in a 20-foot radius sphere centered on that point must make a Dex save (DC based on your Charisma). On a failure, creatures take 2d6 fire plus 2d6 necrotic damage for each Death Point expended, or half as much on a success.

    Ok, a lot to break down here:

    Being Undead is certainly the thematic culmination of your transformation into a Death Knight. It does, also, create problems if you have a Cleric in the party that wants to Turn Undead. Thankfully, healing spells now work on Undead and Constructs, so there's no real problem there.

    The damage resistances are actually quite nice, and the lack of need to eat, drink, or breathe is situationally nice but less likely to come up.

    Hellfire Orb is, of course, an iconic Death Knight ability. At level 12, you'll be able to expend 4 points, which gives you 8d6 fire and 8d6 necrotic damage, which is quite a lot, basically two fireballs at a time. I suspect that if I played one of these, I'd be hesitant to pour all of my points into one of these unless we had a big group of foes that were all pretty beefy. Just two Death Points will give you a Fireball (half of whose damage is necrotic and thus less likely to be resisted).

    The main thing is that it's an option to Nova pretty big: one level later, we can do 5 points and thus a total of 20d6 damage, which is half of a Meteor Swarm (my DMPC dropped one of those on the Tarrasque, and transmuted the fire into lightning to make sure it all went through, and boy is that a lot of damage).

Putting it All Together:

Ultimately, to get the full Death Knight transformation, you'll need to dedicate three feats to this. Paladin is almost certainly the intended class for these feats, but I think a Warlock with a quick Fighter dip to get Weapon Mastery would also work very well.

In the Paladin's case, I'd probably pick the Initiate feat up at level 4 to get me started, then grab Deathly Presence at 8, and finish up the Ascension at level 12, leaving my level 16 feat for something like Great Weapon Master. If I started with a 17 Strength and 16 Charisma, I'd be able to cap Strength by 12. I might actually take GWM earlier (perhaps at level 4 and push everything else back,) and instead pump Charisma or Con with Ascension at 16.

For a Fighter, playing an Eldritch Knight would help so that I could cast the spells using spell slots along with Death Points. With an extra feat at levels 6 and 14, I might pick up an Ability Score improvement to speed things up at level 6, or perhaps take Death Knight Initiate then, after getting GWM, Dual Wielder, or Polearm Master.

For a Bladelock, I'd start with a level of Fighter (a solid plan for any Bladelock) and then stick to Warlock for most of my career, getting Initiate at 5, probably Deathly Presence at 9 (though if I have Fear already at level 6, I might grab a different one - sadly Unholy Steed doesn't boost Charisma), and then Ascension at level 13, after which I might consider putting another level or two into Fighter for Action Surge and maybe a subclass. Naturally, Undead Patron would be a fitting subclass (though any dark-themed one works).

This is a really interesting approach to these transformations - obviously it fits into the existing framework of feats, and does present a bit of a challenge given the pretty huge commitment if you want to go all the way. That might keep it balanced, though. I do think that the addition of a special resource to fuel your spells that isn't just like "once a day unless you have spell slots" does make this a lot better than a lot of feats that grant spells.

I'm super curious to see what book these might come out in, but given that we still don't have a confirmed Dark Sun book, I'm not holding my breath (though if I were a Death Knight, I could).

Next, we'll finish up this UA with the other, arguably more iconic undead monster's path: the Lich.

UA: Demonic Sorcery

 As the second-most represented fiends, I still kind of feel like demons wind up underrepresented in D&D. I think there's an assumption that, because of their chaotic nature, they must be mindless brutes and cannot be the slick, conniving schemers that Devils are. I disagree with this characterization. I have a whole rant about how law and chaos are more about institutionalism versus personalism, and how demon lords have to be very clever to make sure they maintain control of their forces, and they're careful not to anoint a successor so as to ensure that they are irreplaceable.

But yes, demons: gross, malformed, unpredictable, wild. This is chaos mixed with evil, and thus less likely the whimsical whack-a-doodle of the Wild Magic Sorcerer. Let's see how they work:

Demonic Spells:

1st level: Detect Magic, Entangle

2nd level: Misty Step, Spider Climb

3rd level: Dispel Magic, Gaseous Form

4th level: Confusion, Hallucinatory Terrain

5th level: Contact Other Plane, Hallow

    Misty Step is a spell I take on basically anyone who can get it. Detect Magic and Dispel Magic are good utility spells to have around. Confusion is helpful because it gets around Charm immunity. Some solid ones here.

Level 3:

Abyssal Rupture:

When you spend at least 1 Sorcery point as part of a Magic action or bonus action on your turn, youc an unleash one of the following effects (once per turn).

Demonic Lash: One creature within 20 feet you can see takes 1d4 Slashing damage, and if it's Large or smaller, you can pull it up to 10 feet closer to you.

    Rare that a Sorcerer wants a creature to be closer to it, but there are scenarios where it could be good.

Fiendish Carapace: Until the start of your next turn, attacks against you have Disadvantage.

    This is sure to be the default option, giving you a little more survivability as a squishy sorcerer.

Level 6:

Abyssal Aura:

(Get Ready)

When you use Innate Sorcery, you can infuse chaos into your surroundings. While Innate Sorcery is active, you warp reality in a 10 foot emanation around you. You roll a d6 to determine the effect. If it has a DC, you use your spell save DC.

You can do this once per long rest for free, or spend 2 Sorcery Points (no action required) to restore your use.

1: Sticky Webs: The area becomes difficult terrain for your enemies. Each enemy that starts their turn in the emanation must succeed on a Strength save or be restrained. They can take an action to make an Athletics check against your DC to end the effect.

2: Caustic Ooze: The area becomes difficult terrain for your enemies. Each enemy that starts their turn there takes 1d6 Acid damage and must succeed on a Dex save or fall prone. At level 11 this becomes 2d6 and at level 16 it becomes 3d6.

3: Terrifying Screams: Each enemy that starts in the emanation takes 1d6 Psychic damage and must make a Wisdom save or be frightened until the start of their next turn. The damage increases to 2d6 at 11 and 3d6 at 16.

4: Enthralling Spores: The emanation is Heavily Obscured for creatures of your choice. When you reach level 11, enemies that start in the emanation must make a Wisdom save or be charmed by you until the start of their next turn.

5: Poisonous Foliage: The emanation is lightly obscured. Each enemy that starts its turn in it takes 1d6 Poison damage and must succeed on a Con save or have the poisoned condition. Again, the damage goes up to 2d6 at 11 and 3d6 at 16.

6: Enervating Bones: Spectral Limbs erupt from the ground in the emanation. Each enemy that starts its turn in the emanation takes 1d10 necrotic damage and cannot regain hit points until the start of its next turn. The damage goes up to 2d10 at level 11 and 3d10 at level 16.

    Well, first off, I stand corrected: This is the reason to use Demonic Lash.

    Notably, you can't choose which of these features you get, but they're all at least pretty comparable in utility. They mostly avoid friendly fire (the foliage does lightly obscure things for everyone, but that just means disadvantage on perception checks). This is a Sorcerer who is going to want to be up close with foes, which means you should build accordingly.

Level 14:

Abyssal Conduit:

Your Abyssal Aura is now a 20-foot emanation. You can also roll twice on the table and pick between the effects you roll. If you roll the same number twice, you can pick any of the options.

    So, this is both a wider aura and more control over what you get, which are both good. 20 feet is still fairly close, though.

Level 18:

Fiendish Servant:

You can cast Summon Fiend without a Material Component (you also, presumably, get it prepared for free - it's not typically a Sorcerer spell, I believe). You can also cast it once for free per long rest, though when you cast it this way, you must choose the Demon form for the summoned fiend.

    I love the Summon spells, and Fiend is a very good one. The Devil version has the highest damage potential (and also both flies and has a ranged attack, so it's pretty resilient) but the Demon form is also pretty good, and since it's a free casting, this is just gravy. A free 6th level spell per day is not bad at all.

    Part of me wishes this came earlier, but I don't know that I'd want to delay Abyssal Conduit to do so.

Overall Thoughts:

    However you build this character, you need to make a Sorcerer who can stand to be close to its enemies. The Abyssal Carapace option does help a bit, but I think you might want to take other defensive features into consideration.

    The subclass puts a lot into Abyssal Aura. You'll probably want to use it each fight, but you might not always want to use it. That might be ok: we get features that don't rely on it. I think the tough thing is when you use it and get an option that you really don't want, like Poisonous Foliage when you're fighting things immune to poison. Like, say you're fighting a bunch of devils. You'll still want to use the feature because the other possibilities are good against them, but if you happen to roll a 5, you've got something that's kind of worthless. And you'll need to both spend Sorcery Points and another use of Innate Sorcery to try for a different aura on your next turn.

UA: Hell Knight Fighter

 The Nine Hells are evocative, but I also sometimes feel like they get overexposed when we talk about the outer planes. Modeled on Dante's Inferno, we're sort of queued up already to recognize its structure, its nine circles. In Asmodeus, we have a Lucifer without an official Abrahamic God in D&D's polytheistic cosmos.

So I get it, it's compelling.

I might be a little more annoyed by this focus if not for the fact that this UA does give us a corresponding subclass to the chaotic evil plane of the Abyss.

I could very much imagine an evil paladin of the Nine Hells, but giving Fighters some infernal power kind of reflects the more conviction-agnostic characterization of the Fighter class. There are various suggestions on why you might have become a Hell Knight, and while the subclass is very villain-coded (you will be sending souls to the Nine Hells when you kill) there are some scenarios where you might not have taken up this role willingly.

Let's get into mechanics:

Level 3:

Diabolical Gift:

You get two benefits:

Devil's Sight: You can see normally in Dim Light and Darkness, both magical and nonmagical, within 120 feet.

    This is worded just like the Warlock invocation of the same name, and notably is not Darkvision, which means that you should be able to see in color, and I think you could argue that "seeing normally" would be as if it were all bright light. While you might still consider the Blind Fighting style at level 1, this is going to cover a lot of what it covers, and better.

Devil's Tongue: You know the Infernal language, or another of your choice if you already speak Infernal.

    A "ribbon" that could be very useful in a devil-themed campaign (and if you're a DM with one of these in your party, you'll want to have some devils pop up - though their immunity to fire damage might hinder this character a little if they're fighting them).

Hellfire Weapon:

When you take the attack action, you can imbue a weapon you are holding with hellfire, turning it into a Hellfire Weapon. It remains transformed this way for 10 minutes or until you use the feature again, die, or the weapon gets more than 5 feet away from you for 1 minute or more. You can also end it early, no action requried.

While transformed, the weapon emits dim light out to 5 feet and you can choose to deal fire damage with it instead of its normal damage.

    The light isn't terribly useful given our Devil's Sight, and might actually be a hindrance, but it's certainly cool conceptually and can be useful if we need fire damage to take advantage of vulnerabilities or stop regeneration.

Infernal Wound:

We're not done with level 3!

You have one Infernal Wound die, which is a d6.

Once per turn when you hit a creature with your Hellfire Weapon, you can deal extra fire damage equal to one roll of your Infernal Wound die and give the target an Infernal Wound.

While wounded in this way, the creature takes fire damage equal to one roll of your Infernal Wound die at the start of each of its turns. The effect lasts for 1 minute, until the target regains hit points, or until the target or a creature within 5 feet of it takes an action to stanch the wound. A target can be affected by only one instance of this feature at a time.

You can use this feature Con times per short or long rest (minimum 1).

    This is pretty great, actually. A d6 isn't huge, and weirdly the die never gets upgraded, but it's a no-save DoT that requires someone's action to end. Put this on a troll and you're in fantastic shape. It also has the crit-smite advantage of being able to wait for a critical hit to use (though it's probably worth it on any hit just to get the wound ticking on the target).

Level 7:

Advanced Wounds:

When you roll a 6 on the Infernal Wound die (presumably either on the initial hit or the ticking damage) you can apply one of the following effects:

Purulence of Minauros: Caustic pus (gross) erupts from the wound. Each creature in a 5-foot emanation originating from the target takes acid damage equal to your Con modifier, and the target has the poisoned condition until the start of its next turn.

    Two problems: first, if you're in melee, that damage is going to hit you (unless you have a reach weapon - not a bad idea for this subclass). Also, if you get this on the initial hit, they might not do anything until the start of their next turn. Granted, for the ticking damage, this could poison them right at the start of their turn. (I also assume they don't take the acid damage given that an emanation goes out from them. Maybe I'm wrong?)

Rupture of Cania: the wound explodes with arcane energy, dealing Force damage to the target equal to your Con modifier.

    This adds insult to injury - they're already taking 6 damage from the wound, and now they're taking maybe three more. Good in a strictly single-target situation.

Stygian Gangrene: Infernal rime spreads out from the wound, dealing Cold damage equal to your con modifier to the target and preventing it from taking reactions.

    Oh, actually, this is better than Rupture of Cania unless the target is resistant or immune to cold damage. I feel like Rupture of Cania needs something more.

    The overall feature here will only come around about 16.7% of the time (for now) but luckily we have more at level 7:

Hell-Forged Equipment:

While wearing armor or wielding a shield (likely for a Fighter) you have resistance to Fire damage.

Also, damage from your weapons and fighter features ignores resistance to fire damage.

    Unlike resistance to poison or necrotic damage, as we saw with the Pestilence Cleric, fire resistance is actually quite common, including nearly all non-Devil fiends (devils tend to be fully immune). That's really helpful. And fire damage happens all the time, so having resistance to it is great (it even helps you when traveling through hot climates).

Level 10:

Hellfire Surge:

When you use your Action Surge while wearing armor or wielding a Shield (again, likely, unless you're like a Fighter/Barbarian multiclass) you can superheat your equipment, erupting in a 10-foot emanation. Each creature of your choice must make a Dex save (DC based on your Con modifier). On a failure, they take fire damage equal to your Infernal Wound Die (again, this is always a d6) and are burning (which is now a Hazard that deals 1d4 fire damage at the start of a creature's turn). On a success, they take half damage and are not burning.

    While certainly limited in use, this is an AoE DoT you get as a Fighter. Get in the thick of a bunch of enemies and light them up.

Level 15:

Blister of Avernus:

Your hellfire deals painful, boiling blisters (gross). When you roll a 6 on your Infernal Wound DIe, you can roll another d6 and add it to the damage. The maximum number of d6s you can add to the Infernal Wound's damage is 3.

    So, we might be hitting a point where the lack of a die upgrade is actually better for us, as we have a higher chance of rolling the max. The chance of getting a third die is 1/36, but this will get more likely with our level 18 feature. Between this and the Advanced Wounds, we get sometimes get a really lucky burst of damage, but I think you could argue this is a bit of a double-dip.

Level 18:

Hellfire Condemnation:

Whenever damage from your Hellfire Weapon or Infernal Wound reduces a creature to 0 hit points, the creature dies and its soul rises from the River Styx as a Lemure in a layer of the Nine Hells of your choice in 1d4 hours. If not revived before then, they can only be returned to life with a Wish spell.

    Theoretically, this could be useful against a foe that can escape death. Would this kill an Arch-Hag without needing to find their anathema? Does this prevent a Lich from coming back via its Soul Jar? That might be far too powerful for monsters that have built-in ways to come back.

    On the other hand, does this also prevent us from subduing targets non-lethally? I guess we can discharge our Hellfire Weapon, but while the flavor of this feature is cool, I think we need to revisit its implementation.

Infernal Bargain:

When you roll your Infernal Wound Die, you can treat a roll of a 1 as a 6.

    This is actually enormous for our earlier features: doubling the chance that we activate both Advanced Wounds and Blister of Avernus. The d6 now has an average damage roll of 4 1/3 (up from 3.5) and we now have a 1/3 chance to activate Advanced Wounds. The chance of getting three dice on a Blister of Avernus is now 1/9.

Overall Thoughts:

    This subclass is really interesting and different. Fighter subclasses come in varying levels of complexity, and while this will seem complex at first, I suspect that it will wind up being fairly simple after any significant experience playing it.

    I don't think we're looking at the same power level as an Eldritch Knight or Battle Master, but it's still pretty cool. Letting us set our DCs via Con also lets us pour all of our ability score stuff into just two stats (Battle Masters have the advantage of being truly SAD, but this is better, I'd say, than needing Intelligence on top of Strength/Dex and Con).

    It's kind of flavorful that these mortal knights empowered by the Hells are actually far less effective against Devils, who are almost all immune to fire, while they're quite capable against Demons, Yugoloths, and other fiends who are merely resistant.

UA: Circle of the Titan

 When "One D&D" was in testing before it became 2024 D&D and then 5.5, there was a controversial initial redesign for the Circle of the Moon Druid. Instead of picking existing creatures from the Monster Manual, the Moon Druids would take one of three template stat blocks that scaled with their level.

There were two problems: the stat blocks were limited to just a Land, Sea, and Air version, lacking the nuance of special creature abilities that would make a Wolf and a Bear, for example, distinct from the other, and, more crucially, the stat blocks sucked - their AC was lower than a Druid was likely to have just in their humanoid form, among other ideas.

However, when the next playtest reverted it to picking stat blocks, even if there was some relief from those who liked to keep things as they were, I was among several people who lamented this backpeddling - template stat blocks (like the various Summon spells) are actually great, and solve a lot of problems with level scaling and keeping things relevant.

When Honor Among Thieves came out and nerds pointed out that the party's druid ought not to be able to turn into an Owlbear (being a Monstrosity rather than a Beast) I actually did some homebrewing to create a Circle of Monsters subclass that used templates to transform the Druid into monstrosities that could be anything from Sorrowsworn to Owlbears to Mimics, borrowing that earlier design but making stat blocks that I felt, at least, were far better.

It looks like WotC is doing something similar.

While the other three stat blocks here are pretty firmly evil-coded, there's something a little less moral about the Druid subclass. This is basically the "wild shape into the Tarrasque" subclass, and like the Tarrasque, its outlook is more neutral - perhaps opposed to the excesses of civilization encroaching on the natural world, but aligned more with chaotic destruction than evil brutality.

This is the only subclass I'm aware of that allows you to eventually become Gargantuan without some spell shenanigans. Let's get into it:

Circle Spells:

Cantrip: Thaumaturgy

1st: Cure Wounds, Longstrider

2nd: (Actually none)

3rd: Fear

4th: Stoneskin

5th: Destructive Wave

    Interestingly, you get two first level spells and no second level. Is this just that there wasn't a good 2nd level option, or an error? Unlike Moon druids, I don't think we get any special exception that allows us to cast our Circle spells while in our Titan forms. Still, Fear is a solid crowd control spell, Cure Wounds is very good in 5.5, and I've seen Destructive Wave used a lot in my Ravnica campaign because it's a friendly-fire-free AoE spell. Stoneskin would be a great spell to have running if you can afford the costly component each time.

Level 3:

Titan Form:

When you Wild Shape, you can adopt the Behemoth, Leviathan, or Insectoid stat blocks instead of the usual beasts. You determine its appearance (there's a table with some suggestions). The stat blocks scale with your Druid level, and gain new features at levels 5, 10, and 14. Each grants twice your Druid level in Temporary Hit Points, 60 feet of darkvision, and is Large size, but you can choose to make them Huge at level 10 or higher, and Gargantuan at level 14 or higher. They are also all monstrosities. Each gets Multiattack at level 5 (basically Extra Attack). Their Rend attacks all use your spell attack bonus and deal 1d8+Wis in, depending on the form, bludgeoning, piercing, or slashing damage, and have a 10 foot reach.

Behemoth:

This stat block has an AC of 11+ your Wisdom. You also have Strength and Dexterity equal to your Wisdom score (your Con and mental stats remain as they normally are). You gain a speed and climb speed of 40 feet.

In addition to the Rend attack, you have Incandescent Breath, which allows you to expend a spell slot of 1st or higher level. Creatures in a 5x60 foot line make a dex save against your spell save DC, taking 2d8 radiant damage per level of the spell slot expended plus your Wisdom modifier on a failure or half as much on a success.

    So, if you do this with a 3rd level spell slot, assuming a +4 to Wisdom, you're doing 6d8+4, or 31 damage, which is better than a Lightning Bolt (though the line is shorter). Honestly, not bad.

The Behemoth also has Siege Monster, doubling its damage dealt to objects and structures.

At 10th level, the Behemoth gets Rampager: When you enter the space of an enemy that is at least one size smaller than you for the first time on a turn, the creature must make a Strength save, falling prone on a failure. If the creature is already prone, they take 2d6 bludgeoning damage.

    Remember that enemies' space is now just difficult terrain, and if you're two sizes larger or smaller than the target, you can end your turn in the same space. We'll be Huge (or at least we can be) by the time we get this, so we can potentially just sit on a target.

    My sense is that this is probably going to be your default titan transformation, but let's see how the others work.

Leviathan:

This stat block has an AC of 10+ your wisdom, and has a speed of 40 and a swim speed of 40. Once again, your Strength and Dex are equal to your Wisdom, and the other stats don't change.

You are Amphibious, so you can breathe both air and water.

In addition to your Rend, you have a Reaction called Ink Cloud: When you take damage, you can use a reaction to expend a 1st or higher level spell slot and release an inky cloud in a 15-foot radius cube centered on yourself, and then you can move up to your speed. The cube is heavily obscured, and lasts 1 minute or until a strong current or wind disperses it.

    This is a decent escape maneuver, though it doesn't scale like the Behemoth's breath attack. We don't have blindsight, so it won't help us to attack our attacker.

At level 10, we get Toxic Stench: each creature that starts its turn within a 10 foot emanation of you that you choose must make a Con save, taking 2d4 poison damage and becoming poisoned until the start of its next turn on a failure.

    Against targets that can be poisoned, this can be pretty good, but it's very campaign-dependent.

    Naturally, in any underwater adventure, this has got to be your choice, but I think it's not as good as the Behemoth (not sure it needs to have a lower AC).

Insectoid:

This stat block has an AC of 8 + your wisdom modifier. It's much like the other stat blocks except that you get a 40 foot speed and 40 foot fly speed.

You have the flyby feature, and thus don't provoke Opportunity Attacks if you fly out of an enemy's reach.

In addition to your Rend, you have Energizing Pollen: you can expend a 1st level spell slot as an action and emit a cloud of healing pollen. Choose any number of creatures within 15 feet of yourself. You heal a total of 2d8 plus 5 times the spell slot's level, and divide the HP between the creatures chosen.

    So, this is an AoE heal, but not multiplicative. With a 1st level spell slot, this would be an average of 14 healing (Cure Wounds would be around 9+Wis, so from 12 to 14). The scaling is probably not as good (at 3rd level, we're looking at 24 healing compared to a Cure Wounds that does like 31) but the ability to divide it up is really good - fantastic if you need to get multiple allies up from being unconscious.

At level 10, you gain Hive Mind, which allows you to forge a telepathic link with a number of creatures up to your Druid level that you can see and can speak any language. You can telepathically communicate with each other regardless of whether you share a language as long as you're on the same plane of existence.

    I assume this ends when your Wild Shape ends, but this is a pretty strong telepathy ability. Perhaps not obvious in terms of combat utility, but it could be very helpful.

    The downside here, I think, is that the Insectoid has a pitiful AC - at 20 Wisdom, it's a measly 13, which is awful. And while Flyby is good, you don't have the speed necessarily to get very far away from a foe after striking them. Better hope your foes cannot fly.

Level 6:

Dire Impact:

You gain two benefits:

Elemental Rend: When you hit with your Titan form's Rend attack, you can cause it to deal Acid, Cold, Fire, Lightning, or Thunder damage instead of its normal type.

    Less important with the removal of so much resistance and immunity to those types, but this does give you lots of opportunities to deal specific damage types, like fire to shut down a Troll's health regeneration.

Shockwave: Immediately after you assume your Titan form or as a bonus action on subsequent turns, you can expend a 1st or higher level spell slot to create a shockwave in a 15-foot emanation. Each creature in the emanation must make a Con save against your spell save DC or be knocked prone.

    Couple notes: first, this does not prevent friendly fire, though it's not damage, at least. Also, as you get larger, the area of a 15-foot emanation gets bigger. Really, the true 6th level feature is our Multiattack, except that it comes a level earlier.

Level 10:

Primal Havoc:

You gain two features:

Improve Titan Form: You can choose to become Huge when you take on your Titan Form, and you get the aforementioned level 10 features.

Above it All: While huge or larger in your titan form, Difficult Terrain caused by heavy snow, ice, rubble, or undergrowth doesn't cost you extra movement.

    I think there's a chance that players will quibble with DMs over this: are stalagmites in a cave the same as rubble? Does magical plant growth like from the... Plant Growth spell count as undergrowth?

Level 14:

Monstrous Appetite:

You gain the following benefits:

Gargantuan Size: Your titan form can now be Gargantuan.

Grappling Rend: Once per turn when you are huge or larger and hit a creature with your Rend attack in Titan form, you can make them grappled (escape DC equal to your spell save). You can only have one target grappled this way at a time.

    A saving-throw-free grapple as part of an attack is pretty good, and note that the target's size doesn't come into play here, so you could actually grapple a fellow gargantuan creature.

Swallow: As a bonus action while you are Gargantuan, choose one large or smaller creature you are grappling. The target makes a strength save against your spell save DC. On a failure, the target is no longer grappled but is now restrained within your stomach and is swallowed. A swallwoed creatuer is blinded and restrained, has total cover against attacks and other effects outside your stomach, and takes 2d8 acid damage at the start of each of your turns. You can have a number of creature swallowed equal to your Wisdom modifier, and you must maintain concentration on keeping the creatures swallowed. If you lose concentration or leave your Titan form, you regurgitate the creatures, who fall prone in a space within 10 feet of you.

    This is awesome. It's not quite the 16d6 acid damage that the Tarrasque does to a swallowed creature, but it's actually kind of just solid crowd control. You both need to hit the target and they need to fail a save, so it's not super-reliable, but if you can protect your concentration with things like War Caster and maybe Resilient: Con, this could be a great way to keep foes out of the fight for a bit.

Overall Thoughts:

    I love this subclass conceptually, and I really like it mechanically. I'm a little concerned that the AC is too low (a Moon Druid by the time they cap their Wisdom has an 18 AC in Wild Shape) and the Temp HP is also lower than a Moon Druid's, so while these scale better for attacks (rather than having flat attack bonuses, this goes up with your spell attack) I worry that these Titans will be surprisingly squishy.

    Still, I'm sort of jumping for joy that WotC has presented a Wild Shape-centric alternative to the Moon Druid that uses templates, and the flavor here is top-notch. I'd be really tempted to play this, which is a pretty solid endorsement.

UA: Pestilence Domain Cleric

 Plague and contagion is such a universal human experience, and one that, until shockingly recently, we really didn't understand. There are a lot of things that can go wrong with the human body, but the existence of microbes like bacteria and viruses (are viruses technically microbes? I know they're not considered alive) is something that we've only known about for the better part of two centuries. Thus, the suffering, pain, and horror of plagues was historically connected to supernatural forces - the presence of evil spirits or perhaps the wrath of an angry god.

It's hard to imagine a lot of good deities who would be associated with Pestilence, though as someone of Jewish ancestry, I'm well aware of a recent holiday that was all about the divine invocation of plagues used to punish the Egyptians for holding our ancestors in slavery (a status that is debatable or even dubious historically, but it's a pretty powerful story).

I'm a big fan of good characters with evil powers, and all of these subclasses could probably fit into this. Perhaps you're on a mission of divine vengeance or punishment, and maybe you have to grapple with the morality of that.

Flavor aside, let's leap into the mechanics.

Domain Spells:

1st: Detect Poison and Disease, Ray of Sickness

2nd: Protection from Poison, Ray of Enfeeblement

3rd: Stinking Cloud, Vampiric Touch

4th: Blight, Giant Insect

5th: Contagion, Insect Plague

    To be frank, I don't know that any of these spells are jumping out at me as incredible options. Ray of Enfeeblement can help protect the party from damage if it goes off. One note, though, is that we're going to get another option that makes a lot of poison-based spells much more appealing. (Though I don't think this would apply to the Giant Insect stat block).

Level 3:

Blight Weaver:

You get the following benefits:

Inoculated Soul: You gain resistance to Necrotic and Poison damage, and you cannot be infected by magical contagions.

    Given that they sort of got rid of the idea of diseases in 5.5, this is curious. While the Contagion spell inflicts the poisoned condition, I feel as a DM I'd be forced to rule that this applies. Will we see diseases coming back to 5.5?

Rot and Fester: Damage from your Cleric spells and Cleric features ignores resistance to Necrotic and Poison damage. Additionally, when you cast a Cleric spell or use a Cleric feature that does either Necrotic or Poison damage, you can change that damage to the other type.

    The first part is, I think, nearly useless, as there's almost nothing that's resistant but not immune to either damage types (some vampires might be resistant to Necrotic, but I believe only the Giant Badger has resistance to poison). The second part, though, is huge, because Necrotic is a far more reliable damage type than Poison, so you'll almost always swap out poison damage to Necrotic. Now, how many poison spells do you have? Ray of Sickness is one, but I think all the other spells on your domain list do Necrotic if anything already. And I don't think there are a ton of Cleric spells that do Poison either.

Plague Blessing:

As a magic action, you can present your holy symbol and expend a Channel Divinity to manifest a 5-foot emanation of plague around you or a willing creature you touch for 1 minute. It ends early if you dismiss it, manifest it again, or become incapacitated.

Each creature of your choice that starts its turn in the emanation must succeed on a Con save against you spell save DC or gain 1 Exhaustion level. This cannot raise their exhaustion to a level above your Wisdom modifier (minimum of 1).

    This is, frankly, nutso. It's incredibly rare for a player to be able to inflict Exhaustion on monsters, and this is technically an AoE (albeit a pretty short-range emanation). Even if, without epic boons or other magical means to raise your Wisdom beyond 20, you can't fully exhaust a foe to death with this (that takes 6 levels) Exhaustion is a really nasty debuff, reducing their speed and all d20 tests (including the Con save to resist this) by 2 for each level.

    The fact that you can even slap this on an ally (and it does avoid friendly fire, only infecting creatures you choose) makes it really powerful - start off a fight by putting it on one of your melee allies, and they're going to be potentially forcing that save every turn.

    Is this going to win a fight? No. Con saves can be difficult, because basically every monster has a decent Con. But if it does go off, even just one level is going to reduce their speed by 5 feet and make them less likely to succeed on any d20 test.

    Oh, and if it's a character who is likely to escape the combat, you've put a debuff on them that might take multiple days to recover from.

Level 6:

Virulent Burst:

When an enemy within 60 feet of you is reduced to 0 hit points, you can use a reaction to cause plague to burst from the creature in a 10-foot emanation, or 20 feet if they had any levels of Exhaustion. Each creature of your choice in the emanation must make a Con save against your spell save DC, suffering one of the following effects (presumably your choice):

Putrid Shock: The target is incapacitated until the end of its next turn and its speed is 0 while incapacitated.

Toxic Infection: The target takes 3d6 Necrotic or Poison damage (your choice).

You can use this feature Wis tiems per long rest.

    So, this is pretty effective even if you haven't exhausted them. Once again, it's creatures of your choice, so you can happily do this even on foes that are crowded by your allies. This is useless in a single-monster encounter, or if they're spread out, but against a big horde of enemies, this could potentially hit a lot of targets (and more if the target is exhausted). I think the toxic infection option is going to be great in swarms of weak foes, but especially at higher levels, the Incapacitation effect is going to be a much bigger deal.

Level 17:

Oh right, Clerics only get subclass features at three levels now. Weird.

Vermin Form:

As a bonus action, you can shape-shift into a Medium swarm of tiny pests (like rats, cockroaches, maggots, etc.) While in this form, you retain your general shape, personality, memories, ability to speak, equipment, etc. You're the same except for the following:

Condition Immunities: You have immunity to being Grappled, Paralyzed, Prone, or Restrained

    That's amazing, and I think a really key thing at high levels when you're fighting things that are big enough to swallow you.

Damage Resistances: You have resistance to Bludgeoning, Piercing, and Slashing damage.

    Also great. Not much to say about it.

Movement: You can enter and occupy another creature's space and vice versa. You also gain a climb speed equal to your speed and can climb on difficult surfaces including ceilings without making an ability check.

    Definitely creepy. The Spider Climb ability is probably not as exciting at level 17, but fitting with the flavor.

Plague Bites: When you enter an enemy's space, that creature takes your choice of Necrotic, Piercing, or Poison damage equal to your Wisdom modifier. A creature takes this damage when it enters your space or ends its turn there (one instance of damage per turn).

    At 17, this is pretty small damage, though some fun cheese-grater stuff with a Warlock or other movement-heavy character assisting could get some extra damage out of it.

The form lasts 10 minutes unless you end it early, become incapacitated, or die. You can use this once for free per long rest, or spend a 5th or higher level spell slot to restore your use of it.

    The damage potential of this is not all that exciting, but the condition immunities and damage resistances probably make it a pretty good feature.

Overall Thoughts:

    There are some really strong points here and some weaknesses:

    Strong points include that Exhaustion is a horrifying condition to impose on your foes, and your ability to do so here is in AoE, so against a lot of enemies with not-particularly-good Con saves, this can be amazing. Likewise, the fact that every one of these nasty abilities avoids friendly fire makes this far easier to use. Indeed, the fact that you can choose an ally to be the vector for Plague Blessing is really good.

    Weaknesses are that the domain spells aren't all that exciting, the subclass features lean heavily on Con saves, which monsters are often good at... that might be it.

    I think I'd really need to see this in practice, but my gut tells me this could be a really nasty subclass, less about pumping out damage than totally debilitating your foes, which is a strong strategy.