The otyugh is an old-school monster, dating all the way back to Advanced Dungeons and Dragons—and in all that time, debates have raged endlessly over how to pronounce its name. Countless gamers over the years have made their best guesses, usually settling on something like oh-tee-yug, while the Final Fantasy video game series has adopted the pronunciation oh-tyoo (second syllable stressed, to rhyme with “through”). But according to the seemingly authoritative EN World D&D Pronunciation Guide, citing a 1985 Dragon magazine article, it’s ot-yug; that’s the one I’d go with.
The Monster Manual categorizes otyughs as aberrations, not monstrosities, though it doesn’t explain why—maybe because of its Limited Telepathy feature or its odd morphology. It’s not described as extraplanar, it’s not evil, and it’s not especially intelligent; in all respects other than its telepathy, it seems to behave like an evolved creature.
Otyughs are brutes, with high Strength and extraordinary Constitution. They have a well-developed survival instinct, including the ability to discriminate between easy and difficult prey, but despite their ability to communicate verbally in their own language, their Intelligence is animal at best—about what you’d expect of a sign language–using gorilla. Theoretically, it may be possible to bargain with an otyugh, by appealing to its one and only interest: food.
They have long-range darkvision, suggesting a subterranean lifestyle, although you might find one aboveground in places that don’t get much light, such as a thick swamp or jungle or the bottom of a cellar garbage pit. They’re not penalized for moving around in daylight; they simply like the dark better. They can see fine in it, and their prey can’t.
Normally, they’re not even aggressive. All they really want is food, lots and lots of it, and their definition of “food” is much looser than other beings’. An aggressive otyugh is a famished otyugh, whose supply of refuse isn’t hitting the spot. And if an otyugh is attacking you, it’s because it intends to eat you.
So what’s an otyugh going to want to talk about with this Limited Telepathy it has? Probably, there’s only one thing it ever has to say: “Hungry.” Will a player character even understand the message it’s being sent? Probably. That is, the otyugh’s telepathy is coherent enough that the PC will understand that some other, psychic creature is trying to tell him or her that it’s hungry—the PC won’t mistakenly start to feel that he or she is hungry.
Wise PCs will chuck some food the otyugh’s way and steer clear of it. Foolish PCs may ignore the warning, or worse, approach to investigate. A hungry otyugh will attack when they come within 10 feet of it. A starving otyugh will attack when they come within 40 feet.
The otyugh’s Multiattack consists of a bite attack and two tentacle attacks, but the tentacle attacks come first, because they can grapple and restrain. If the first tentacle strikes, grapples and restrains its target, the second tentacle will grab for a second if one is within reach; if not, it smacks the target held in the first tentacle a second time. The otyugh always directs its bite attack at a grappled target, if it has one, because it makes this attack with advantage. If an otyugh starts its turn with a grappled victim in one or each of its tentacles, it uses its Tentacle Slam action instead, to try to bludgeon them into submission.
Since the goal of an otyugh is to consume its victims, I’d add one thing to this creature’s features: that a grappled victim reduced to 0 hp by the otyugh’s bite attack is eaten. You can use the remorhaz’s Swallow feature as a model, though I’d reduce the digestion damage from 6d6 to 4d6 and allow it to be used only against an unconscious target. If an otyugh reduces its victim to 0 hp using a tentacle attack or Tentacle Slam, it must use an additional bite attack to Swallow the victim.
As a DM, though, I wouldn’t throw an otyugh at a party if it had a real chance of getting to eat one of them. An otyugh makes an uninteresting boss monster; it functions better as a hazard than as a nemesis. An otyugh encounter shouldn’t present greater than Medium difficulty to your players (see “Combat Encounter Difficulty,” Dungeon Master’s Guide, pages 82–83).
Hoard of the Dragon Queen includes an otyugh encounter in Episode 6: Castle Naerytar. If you’re using the milestone experience rule, your PCs will be level 5 when they encounter it, which is about right. But if you’re using standard XP progression, and any of them is level 4 or lower, it could give them real problems. Rather than nerf the otyugh’s stats or alter its behavior, find some way to make sure your PCs have some sort of advantage going into the encounter, such as overhearing lizardfolk or bullywugs talking about the “garbage beast” in the midden, so that they know it’s there.
An otyugh doesn’t move around if it doesn’t have to, and it won’t usually have to. If it’s hungry enough, though, and its potential meals back away from it, it will move toward them at normal speed. It will give up and retreat only if it’s seriously wounded (reduced to 45 hp or fewer), and if it’s starving, even that won’t be enough to deter it.