Mind flayers are like classic pulp supervillains: brilliant, twisted, scheming, always wanting to take over the world—but first, they have things they want to do your brain. They even wear outfits straight out of Flash Gordon. And yet the fifth-edition Dungeons and Dragons mind flayer feels unsatisfying to me, maybe because, as written, it just isn’t very efficient.
The Monster Manual flavor text characterizes them as “psionic commanders,” declaring, “Mind flayers possess psionic powers that enable them to control the minds of creatures such as troglodytes, grimlocks, quaggoths and ogres.” And the feature they use to accomplish this is . . . dominate monster, which they can use once per day, and which affects one creature, requires concentration and lasts for one hour?
This is paltry. It’s unworthy of a supervillain. I’ll talk about the tactics of the mind flayer as written, but then I’ll go on to talk about how to make a mind flayer capable of enthralling, and keeping enthralled, more than one minion at a time.
Mind flayers’ physical abilities are nominally average to slightly above average, but they’re no better than the average adventurers’ and downright weak compared with most intermediate-level boss monsters. Mind flayers compensate with exceptionally high mental abilities across the board, especially in Intelligence, and with proficiency in all mental ability saving throws.
They also have proficiency in Stealth, Perception, Insight, Persuasion and Deception (also Arcana, but that’s strictly for flavor). They’re resistant to spells and other magical effects, and in addition to dominate monster, they can also cast detect thoughts and levitate at will and plane shift once per day on themselves.
Their primary method of self-defense is the Mind Blast action, which has a recharge and which affects every creature in a 60-foot cone, potentially stunning them. Secondarily, they can attack with their face-tentacles, which both grapple and potentially stun their target on a hit, and Extract Brain against an already incapacitated (by either stunning or some other means) and grappled opponent.
But the mind flayer doesn’t really want to use this secondary attack against a still-functioning opponent. Ideally, no opponent should ever get within melee range of a mind flayer under its own power. Instead, mind flayers would rather incapacitate their opponents at range, then move in to consume their brains. Even a cornered mind flayer will prefer Mind Blast, if that action is available, over a melee attack with its tentacles.
To ensure that its enemies don’t get close, a mind flayer uses minions to run interference. The creatures listed above (troglodytes, etc.) are good choices, as are enthralled humanoid commoners. Grells also make a good fit thematically, continuing the brain and tentacle themes of the mind flayer and its dogsbody, the intellect devourer.
PCs attacking a mind flayer in its lair will have to fight their way through waves of minions before ever getting near it, and in the meantime, it’s hanging back 60 feet behind the action, levitating about 10 feet in the air so that melee attackers can’t reach it, and Mind Blasting anyone who breaks through the line.
Mind flayers value their survival highly, but like a pulp supervillain, they value their schemes as well, and they won’t want to give up their lairs if there’s any chance at all that they can win a battle, so they’ll hold out until they’re seriously injured (reduced to 28 hp or fewer) before casting plane shift to make a hasty exit.
But this presumes they have only one lair and one scheme going. If they’re up to different things, and the lair the PCs are attacking isn’t the most important one, they’ll cut their losses earlier, after being only moderately injured (reduced to 49 hp or fewer), and let any remaining minions handle the job from there.
Now, how to make a mind flayer capable of taking over more than a tollbooth? I’ve thought of a few possibilities, though I’m sure there are others (please feel free to share in comments):
- Borrow the vampire’s Charm feature. This affects only one creature at a time, but it lasts up to 24 hours and doesn’t require concentration. Still, it doesn’t do anything to address the real conundrum of dominate monster, which is how the mind flayer keeps its minions enthralled once the effect wears off.
- Borrow the aboleth’s Enslave feature. Again, this affects only one creature at a time (though the aboleth can do it three times per day, which is an improvement), but it lasts indefinitely, although the target can repeat its saving throw once per day if it can get a mile or more away (a risk easily mitigated by commanding the target never to venture more than a mile away). It also doesn’t require concentration.
- Change dominate monster to geas. Although it affects only one creature at a time, it lasts 30 days and allows no subsequent saving throw after the target fails the first one, not even if the target takes damage. It also leaves open the possibility that targets can resist the commands they’re given—but gives them a nasty psychic shock if they do. The one drawback is that it takes a full minute to cast, not a single action, but if you like the idea of having a mind flayer take over a PC’s mind in the middle of combat, you can handwave that, particularly considering that geas is a much lower-level spell than dominate monster.
In each of these cases, I’d change the listed saving throw to a DC 15 Intelligence save, to match Mind Blast and the mind flayer’s tentacle attack. Following the example of the aboleth’s Enslave feature, you might also allow a mind flayer three uses of Charm or geas per day rather than just one—or, maybe, give it Enslave as written, plus a single daily use of geas.
This will give an entrepreneurial mind flayer a chance to build up a decent-size posse around its new base of operations in a reasonable amount of time. In case it wasn’t obvious, all of these choices replace dominate monster.
With any of these powers, a mind flayer has a new combat option: mind-control a PC into fighting against his or her allies. That will be its second-choice tactic, after Mind Blast. Enslave or a fast-cast geas is better for this than Charm, however, since Charm allows so many saving throws, the turned PC probably won’t stay turned for more than a round, unless his or her allies scrupulously refrain from fighting back. (You can do this with dominate monster too, which is why I suppose this spell was included among the mind flayer’s features in the first place, but the fact that it requires concentration means the mind flayer can’t dominate an opponent and levitate at the same time. Bogus.)
The obvious thought is to use this feature against the biggest, baddest fighter subclass in the party. It’s obvious to us because we don’t have Intelligence 19. The mind flayer, however, does. It can compel other monsters to form an offensive line, it can psychically debilitate anyone who tries to charge it, but it knows what its one real vulnerability is: archers.
Mind flayers resist magic, but they don’t resist arrows. Against the mind flayer’s middling AC, a ranged attacker more than 60 feet away—especially a ranger with Colossus Slayer, specializing in Archery—will make quick work of it.
That’s the one the mind flayer will want to mind-control. Plus, if you’re using the Charm or Enslave alternative rather than the geas alternative, a ranged weapon attacker is likely to be positioned farther away from his or her allies, so he or she won’t take damage so soon and therefore is likely to remain enthralled longer.
Now, you might say, “But mind flayers aren’t the real boss monster. They usually live in colonies, not by themselves. The real boss monster is the elder brain.” Yeah, you’re right about that. But there are two problems here. First and most important, the MM doesn’t give stats for an elder brain. (Maybe Volo’s Guide to Monsters does.
If so, when I have that book, I’ll come back to this topic.) The second is that, for an intermediate-level adventuring party, one mind flayer commanding a decent number of minions is more than challenge enough. As I suggested before, let’s say this is one with an entrepreneurial spirit. Maybe it’s laying the groundwork for others to follow. Or maybe, as the MM flavor texts suggests, it’s simply a rogue or an outcast.