On Magical Big Bads

 When you DM, how do you think about spellcasting?

I've always struggled with spellcasting enemies. The premise is strong - fantasy is awash in magically-empowered villains. Indeed, in some works, the very use of magic more or less makes you a bad guy, but even in those where magic is something to be practiced by people of all kinds of moral alignments, it's a major trope.

So, it makes perfect sense for a big bad in your D&D game to have a whole bevy of spells that they can cast. Ancient wizards (or Ancient Undead Wizards, in the case of a Lich) are a great option for a Dark Lord that will be the final boss of your campaign.

And it seems only reasonable that in a world where player characters can cast magical spells, it stands to reason that periodically, they should come across foes who can as well.

The thing is... it's always kind of a pain to track. There are a million things that a DM needs to keep track of, and tracking each spellcaster foe's spell slots is a fairly big burden. Admittedly, this can be a bit easier if it's just the one major spellcaster, like a Lich, but even then, you've probably got a bunch of villains to handle too.

In his video on Vecna and big villains, Matt Colville, I think, identifies the real issue: spellcasting is a system built for player characters, and it doesn't work as well for NPCs.

As an example, spellcasting stat blocks usually have spells of many different levels. A Lich has spells from 1st to 9th level, and the spell slots of a character who has gotten to level 18. Those first level spells are almost certainly not going to be cast in the course of a battle, and certainly not at 1st level. If a party can't kill a Lich before it's run out of higher-level spell slots, the Lich has almost certainly killed them by that point.

We've heard that future monster books are going to see a revision how spellcasters work, to lessen the burden on DMs running them.

As an example, the updated version of the Warlock of the Great Old One, a statblock introduced in Volo's Guide to Monsters, now has a dagger attack that does an extra 3d6 psychic damage, and an ability called Howling Void, which lets them hit a 30-foot cube, letting creatures within make a Wisdom saving throw, doing 2d8 psychic damage and frightening them until the end of the warlock's next turn on a failure, or half the damage and no fear on a success. Then, there's an innate spellcasting ability which has various spells that can be cast at will or once a day, but none of which are damaging, battle-spells (except Mage Armor, which you can presume they've already cast on themselves). That and a Whispering Aura that deals 3d6 psychic damage to nearby creatures within 10 feet of the Warlock's choice if they fail a Wisdom saving throw, and you've got the whole statblock, more or less.

Compare this to the original, Volo's Version. Here, the Whispering Aura is the same, but the statblock has a full Warlock spellcasting ability along with its Innate Spellcasting (which is clearly meant to simulate eldritch invocations).

The older version is more flexible, and is, thus, arguably more powerful. But as a DM, I can really imagine grabbing the new version and saying "ok, I want this NPC to do some damage. I can put out about 30 with two dagger attacks, or if I want more crowd control, I can use his Howling Void". Now, I don't need to look up all the different spells he can cast.

What I am really eager to see is how they apply this treatment to more powerful foes.

Again, the Lich is certainly the most iconic monstrous spellcaster in the game. As such, it will need to retain the utility that make it a really legendary (both in the mechanical and cultural senses) monster. But I'd also like to see what their take is on "this is what the lich does when they want to kill some heroes" ability.

Actually, I think Dragons serve as a pretty good model on how to do this - dragons come with various bells and whistles, but ultimately, their breath weapon is the way that they take care of business. If you're not a dummy like me and forget that not having a Hover flying speed still allows them to end their turn in the air (it just means that getting knocked prone is bad) and thus you can keep the dragon flying out of reach of the Barbarian and the Fighter until its breath weapon comes back, the awe and terror of what a dragon can do becomes apparent - big blasts of damage during the short window when you can actually damage it.

This is a pretty big shift in monster design philosophy, but I think it could really make the game easier to run, especially at higher levels. I remember running by level 18 one-shot and breaking out Orcus as the big bad for them to fight. But I found myself kind of shocked that what he can actually do on any given turn is pretty underwhelming. You've basically got Finger of Death, Power Word Kill (which won't actually do anything until you've done a fair amount of damage to a level 18 party,) Blight, Circle of Death (which, big radius, but it's just a Fireball's worth of damage, which isn't really that much at this level) and then his melee attacks, which, though they have a +19 to hit and thus probably will, only do a total of about 68 damage per turn.

Sure, he can summon a whole bunch of undead, but I do feel like the demon prince of undeath should have some massive necromantic ability that dwarfs anything a player necromancer could pull off. (Which, again, his summoning 500 HP worth of undead isn't nothing - you can get two death knights and a dracolich.)

Right now, I'm slowly herding my party in my Ravnica game into a quasi-dungeon that leads to a true dungeon, at the end of which is the Golgari member of the Phyrexian conspiracy to take over Ravnica. I'd always intended to use the Devkarin Lich stat block for him, though I do have a couple issues to anticipate:

The first is that the Devkarin Lich is actually pretty low CR for what they can handle at this level. The party is all level 13, and we usually have 5-7 players active at a time. A Devkarin Lich is CR 14. I'm tempted to instead just re-skin the Jarad vod Savo stat block (and in fact, I've sort of justified it in that the bad guy has captured the Golgari Guildmaster and is drawing on his energy to try to open a portal to New Phyrexia so that the glistening oil they get stops getting diluted by exposure to the spark of the planeswalker the Phyrexians have been using to transport the oil from NP to Ravnica).

Jarad does have some interesting abilities of his own, but I'm also tempted to take the Devkarin Lich as a framework and build something that anticipates the design for these new types of monsters.

Of course, in the back of my mind, I'm always worried about the potential for a TPK. My general belief is that if a player character dies, that's either bad luck or bad strategy. If there's a TPK, the DM probably made the encounter too hard.

Right now, rather than buff the boss fight to an extreme (though it will have multiple phases with some big enemies) I'm hoping instead to make the dungeon before it a bit more grueling. They're going into the Plagueworks, and I think that while inside, they're going to periodically (probably once for each wing they enter, of which there are three that will each have one or two combat encounters) have to make Con saves against the noxious fumes everywhere and take a significant though perhaps not massive amount of poison damage on a failure, to just keep some ticking damage on them and drain their resources a bit.

Actually, I almost never use traps. This might be the time to do so!

Anyway, this is getting more specific, and I wanted to touch more on the general issues with running spellcasting monsters/NPCs.