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.