I've had Warlocks on the mind.
I think largely because the D&D character I'm playing currently (in theory our Wild Beyond the Witchlight game in which I'm playing a Rogue is just on hiatus, but it's been like three months) is a pretty classically heroic character (his biggest flaw is that he's naive - a kid just out of Wizard college, though he's now been adventuring for several months, or years in real-time) I've been drawn to the idea of the Warlock, to the idea of playing the morally questionable member of the party. Honestly, my Rogue was sort of meant to be that in Wild Beyond the Witchlight, though his was a bit more of a tragic "did bad things but meant well" kind of character, and being a prewritten adventure, that doesn't play so closely into the plot.
I actually played a Warlock of this very "token evil teammate" variety when I did an Adventurer's League version of Descent into Avernus (DM'd by a friend who got me to play a bit of AL). This character, Old Knox (not his real name) was an elderly Half Elf who acted like a friendly old grandfather (and was, actually, a grandfather, but was estranged from his family) who had spent most of his 160 years trying to make contact with an entity known as the Blade of the Silent City, an ambition that did get one of his former students killed after accidentally summoning a bunch of Shadowspawn.
The Undead patron hadn't yet been released, and wouldn't be AL legal anyway, so I was playing a Hexblade, but while Hexblade was built for going Pact of the Blade, I actually played him as a Blastlock - pretty much everything else about the subclass worked fine that way. But I wanted to play a kind of Shadowfell-associated necromancer character, which felt like a good fit for going to the Nine Hells without having my patron directly involved in events there (again, it was AL and a pre-written adventure, so no real expectation of his backstory getting involved in the campaign).
I enjoyed playing Old Knox a lot, and loved making other players at the table squirm while still playing him on the plausibly deniable side of True Neutral (I think it's important to think of alignments in uppercase and lowercase, and Knox's evil was lowercase - he was willing to do messed up things to get what he wanted, but wasn't intentionally cruel and didn't wish to spread suffering. Indeed, at the end of the campaign, he and the Bard made some very good persuasion rolls that gave us the best ending, in which Zariel abandons evil and becomes an angel again - Knox's argument was that her acts had done nothing to actually stem the tide of chaos, and had only invited more chaos into the cosmos).
Now, the title of this post is a question: what's the most interesting way to play a warlock?
That has two obvious meanings: how do we RP one, and how do we build one for fun gameplay?
RP is more nebulous: there are countless ways you could determine your character's backstory and the manner in which they interact with others. I do think it's important to consider that Warlocks are a Charisma-based class - you should consider how that is expressed.
It's a little tough: much of even the premise of the Warlock suggests something of a scholar of forbidden knowledge, which would seem to make Intelligence important for them. That being said, Bards are also collectors of stories and songs and such, though it's their performance of those things that determines how powerful their magic is.
For a Warlock, the obvious way to interpret their Charisma as their primary stat is the idea that they've talked their way into a deal with their otherworldly patron, and so a kind of slick, charming, silver-tongued character can make sense.
However, I think there's another way to think about Charisma, which actually lines up more with how I see it with Paladins: there's an iron will behind your words and actions. A Warlock might just be deeply serious, speaking with force. Perhaps this is just pushing Intimidation over Persuasion, but I think that conviction could be a major part of how you were able to siphon this power off of your patron.
My very first D&D character concept (which I've technically been able to play a handful of times) is a Great Old One Warlock whose mind is being made more and more alien the greater his connection to his patron grows. While I came up with the character in 2015 or so, I think the style of Great Old One that I really think fit well was the Board from Control (a video game I write about a lot here). Basically, Great Old One less in the gooey Lovecraftian manner and more in the Monoliths from 2001, sort of inorganic and questionably sentient variety.
Conrad, this character, is, like a lot of characters I gravitate toward, a pretty purely good character, but the danger of his connection with this eldritch world is what creates conflict for him. Old Knox went into his Warlock career with his eyes fully open, and Conrad probably doesn't even know that a Warlock is what he is.
Actually, there's another character I got to play only very briefly. Aldric is a Reborn Undead Warlock, and was basically an ambitious courtier whose court was massacred by a group of Fey, and he was bricked up in the basement of the palace like in A Casque of Amontillado. Aldric woke up maybe a century after this happened, contacted by the Grandmaster of an order of cursed knights who had, long before he did, been betrayed by the same fey court and were sealed in their chivalric order's tower. Basically an entire knightly order of death knights (though cursed to their state, at least as far as he knows, not by their own sins but by this betrayal - or at least that's the official story) serves as his patron. Aldric would have a courtly manner, and act very much as a representative of the Order, with a certain lawyerly professionalism and detachment.
And that brings us to mechanics:
Warlocks are pure spellcasters, but also not.
While a Wizard can build out their spellbook and figure out their spell preparations in extremely varied ways, a Warlock has to contend with the fact that, at the best of times, their spellcasting is limited.
Now, it's not that bad: as a 9th level Wizard, I have a single 5th level spell slot. An equivalent Warlock would have two, and would be able to get both back on a short rest, and one more slot with Magical Cunning each day.
It's certainly less than the 14 total spell slots that my Wizard has, but if you figure even a single short rest in there, you're getting 5 5th level spells a day. Having played a Warlock who got up to tier 3, I had 3 5th level slots at any given time, so on a similar day we're talking 8 5th level spell slots (though I was playing the 2014 version that didn't get Magical Cunning until 20) as well as a single casting of a 6th and 7th level spell. It's honestly not that terrible - you just have no "throwaway" spell slots, like how a Wizard at 9th level can be pretty cavalier with their 1st level slots.
This is going to be true regardless of what kind of Warlock you go with, so I think the big question is the following:
Blast or Blade?
Is that too reductive? I think you can build a Warlock around other options, in theory, but I just do not think that it's ever going to be as good. But also, let's weight Blade versus Blast.
By default, I think every Warlock is probably going to take Eldritch Blast. Even if you really want to focus on a Pact of the Blade build, it's such a great cantrip that will always give you a wonderful ranged option.
The question, then, that presents itself is: why go Bladelock?
Well, I will say that I think there's a better justification for it in the 2024 rules than there were in the 2014 rules, but it still requires a few other things to make it worth it. As I see it, the key advantages are that you get to use Martial weapons, and specifically you'll be able to get magic weapons.
Even then, it's a bit of an uphill climb:
If you have Eldritch Blast with the Agonizing Blast infusion (available as soon as level 2) you're nearly treating your cantrip like a weapon, and its cantrip progression is actually just as good (and in tier 4, better) than a Fighter's Extra Attack progression. With a d10 die, you're going to be doing the equivalent damage of a heavy reach weapon like a Halberd or a Heavy Crossbow (or Pistol, though with far better range).
While Thirsting Blade and Devouring Blade will function essentially like a Fighter's Extra Attack features at level 5 and 11 if you take them, Eldritch Blast gets this functionality automatically, and you get a fourth blast while there's no Invocation to give you a fourth Pact Blade attack at level 17.
Now, if you're using a weapon like a Maul, Greatsword, or Greataxe, you'll be able to outdamage Eldritch Blast. But these, as well as the d10 heavy reach weapons (Lances, Halberds, Glaives, and Pikes) all have the heavy property, which means that you'll need at least 13 Strength to wield them without disadvantage. You can, however, use a Versatile weapon that does 1d8/1d10 to get equivalent damage to an Eldritch Blast.
However, here's where you start to get some benefits: Magic Weapons.
Eldritch Blast, unless you can somehow boost your Charisma beyond 20, is never going to do more than 1d10+5 on a hit. Even with something like a Rod of the Pactkeeper, the rough Warlock equivalent of a +X weapon, the damage of your attacks isn't boosted (though the boost to your saving throw DC is very nice).
If we aren't trying to take our Strength to 13 or more, and we're sticking with something like a Longsword wielded with two hands, a +1 Longsword is going to do 1d10+6 when we have our Charisma maxed out, which does start to out-damage Eldritch Blast.
Much rarer, though, if you can get truly powerful weapons like a Vicious Weapon or Flame Tongue (both of which eschew the attack bonus in favor of adding 2d6 damage on every hit - which I think is almost always a better choice) could add up to a ton of damage, especially if you can get to level 11 and have three attacks per action.
But these are tough weapons to come by, and I think in most campaigns, you rarely get weapons that aren't just +X.
Is that worth it, though?
See, Eldritch Blast can be souped up with a lot of other invocations - Repelling Blast is, I think, one of the most powerful ones, and if you can dip into pre-2024 options, combining that with Grasp of Hadar will give you insane battlefield control (and if you or an ally can toss down a Spike Growth, you can do some nasty cheese-grater damage).
What, then, do we get for our pact blade other than marginally higher damage?
One thing I think was a missed opportunity in the 2024 PHB was that Pact of the Blade probably should have also let us use the weapon's Mastery property, which I think is akin to a lot of cantrip rider effects - Ray of Frost more or less has the Slow property, for example.
We can look at some invocations - again, I don't think Thirsting Blade or Devouring Blade really count because they're just letting the weapon keep up with Eldritch Blast/other Martials (though Warlocks I think are the only class other than Fighters and I guess Monks who can natively get three or more attacks in a round without dual-wielding). Eldritch Smite, interestingly, works like how Divine Smite used to work. Unlike the redesigned Divine Smite, Eldritch Smite still has no action required to use it. Its downside, of course, is that Warlocks' pact slots are precious. Divine and Eldritch Smite are good for big bursts of damage (especially if you wait for a crit to use it) but while a mid-to-high-level Paladin can be relatively cavalier with their low-level spell slots, a Warlock, as discussed before, cannot.
Lifedrinker is also a decent little damage boost and an opportunity to heal. It's actually way less powerful than the old version was (which let you just deal extra damage equal to your Charisma modifier) but given how Pact of the Blade has been redesigned, I understand the reason for the change.
But I do think that Pact of the Blade is going to require a fair investment in Invocations to get it all running.
There's also another problem: You're probably going to need to be in melee, and Warlocks are squishy.
The Hexblade subclass from Xanathar's Guide to Everything became the default choice for basically any melee-focused Warlock. In 2024, they did integrate its "use Charisma for your weapon" thing into Pact of the Blade itself, but what Bladelocks did not get was training in Medium Armor and Shields. As a Light Armor class that doesn't focus on dexterity, Warlocks tend to have pretty low ACs, which is less of a problem if you're built around not letting monsters get near you, though it's always good to have a higher AC if you can manage it.
While you can play that subclass still (there's probably going to be an update to it,) I sort of hate that it's still the one subclass that gives you medium armor training. One thing I think was a missed opportunity was to have an Eldritch Invocation that gave you Medium Armor training. Without that, Hexblades are still, arguably, the best subclass to pick if you're going to go with Pact of the Blade, even though some of its features are now redundant.
Now, there's a partial solution here: Take your first level as a Fighter.
This actually grants you a ton of things that the Pact of the Blade option is missing: weapon masteries, fighting styles, and better armor. And if you start off as a Fighter, you also get Constitution saving throw proficiencies, which will help with concentration (though you lose out on Wisdom saving throw proficiency).
I've actually conceived of that aforementioned Undead warlock as starting of Fighter - a plausible enough class for a courtier - so that he can lean into the more martial aesthetic of someone with an order of Death Knights as a patron.
It's just frustrating that this solves so many problems for the Bladelock that it feels almost mandatory. Notably, this will delay those extra attack features, so at least until level 5, I wouldn't take any more Fighter levels to ensure that you're at least getting two attacks and 3rd level spells by level 6.
Can we build a Bladelock that doesn't multiclass? Well, obviously we can, but we're going to have to deal with a few things: if we're just wearing armor, say Studded Leather (something that's cheap enough to get very early on,) we'll have 12+Dex for AC. It's certainly possible to start off with a +3 to Dex, but unless you're willing to truly dump Strength, Intelligence, and Wisdom, you're going to be paying a price in terms of Con, and even then, you're only going to have a 15 AC and probably not be able to raise it much unless you get some great magic armor (a real rarity) or at much higher levels take boosts to your Dex.
Another option, though, is to just accept the low AC and try to figure out ways to survive regardless of that fact. Armor of Agathys is a pretty good spell - it will punish foes for attacking you, which might be good enough to incentivize the DM to avoid hitting you. But also, its Temp HP will help with your survivability (and it scales pretty well through tier 2). Technically, you can even refresh it if you have an additional way to get Temp HP (an Undead Warlock probably wants to start off a fight with Form of Dread, but you could wait until Armor of Agathys is a little diminished).
You might even just consider taking Moderately Armored at some point (though we only have two feat levels by the end of tier 2, and so you're probably going to want to max out Charisma or at least take Charisma-enhancing feats).
One reason I still gravitate toward the Fighter dip at the start is also that you can pretty easily get 13 Strength and thus both wear Chain Mail (you'll need more for better heavy armor) and also wield heavy weapons, and also qualify for things like Great Weapon Master. We're probably leaving those options on the table if we're not going that route, though.
But let's take a step back: Our question is what version of a Warlock is actually most interesting to play?
Here's what I'll say for the Bladelock: you might fight with a number of different weapons over a campaign. Depending on the magic weapons your DM makes available, you might switch between a lot of different ones. Technically you can even use a ranged magic weapon - while the conjured weapons with Pact of the Blade only gives you a melee weapon, the invocation can let you bond with any magic weapon. Now, is a ranged magic weapon really that exciting when you could just use Eldritch Blast? Maybe not.
I do think the Heavy weapon challenge does wind up being a significant issue for the class - the fantasy, I think, is to be a more or less pure spellcaster who nevertheless can use some of the hardest-hitting weapons in the game, but you'll need to invest significantly in Strength to do so, which might be difficult.
Warlocks don't get Conjure Minor Elementals, but if you use Spirit Shroud (from Tasha's) you can get a somewhat less powerful effect, but there are some advantages, like the fact that it is only a bonus action to cast. When cast at 5th level, it'll add 2d8 radiant, necrotic, or cold damage (radiant's probably your safest bet) to each of your attacks. This will scale very nicely with both your extra attacks as well as Eldritch Blast. You need to be within 10 feet of the target (compared with 15 with CME) but if you're focusing on a melee blade build that won't be an issue.
So, we've been talking a lot about optimization, but what about fun?
That's obviously subjective. One advantage that a ranged build will always have is that you're likely to have the opportunity to make your attacks or otherwise do your thing on every turn of combat, without the need to run to get close enough to your target. Eldritch Blast has a very nice range - at 120 feet, it's going to be very rare that you're too far to hit them (Roll20's default map size is a 25x25 square grid, meaning from one end of the map to the other is 125 feet, meaning that if you and your target are on the map, they'll be within range (though if you actually use Euclidian distances, the diagonal will be longer - that's not the default for the game, though)).
Really, I think what it boils down to is how exciting you find weapons to be, and whether your DM is likely to give you interesting magic weapons.
Pact of the Blade feels really good for classes that are multiclassing into Warlock. It's available at a single-level dip, so if you're a Paladin, for example, you can put a level in Warlock and then focus on pumping Charisma to max, as everything will now scale with it.
Going the Blastlock route can work well with a straight-class build, and also plays nicely when multiclassing with other casters (Sorcerers being able to quicken Eldritch Blast, for example, are going to have a ton of attacks per turn).
I do think I'd probably base it a lot on my character concept. I've come up with a lot of Warlocks. I love the concept of a pseudo-Death Knight Undead Bladelock, but I think that my Great Old One Warlock, who is very much focused on the world beyond the familiar and mundane, makes a lot more sense as a Blastlock.