Pictures are from Wizards of the Coast.
Otyugh have a long history in D&D, they always stayed true to their Akaname-like behavior, that of refusal and waste-eaters with disgusting appearances and almost mindless behavior.
My version of the Otyugh isn’t much different though I think they deserve some more interesting background story.
Otyugh’s like all other Aberrations are native to the Far Realm, and these waste-eating creatures thrive in many swamps and even in the most toxic places on that plane. Otyugh’s are immune to poison, diseases and plagues and can eat anything without becoming ill or dying, strangely the only thing they can’t eat are celestial creatures as those will make a Otyugh sick with holy shivers which will eventually slay a Otyugh, an Otyugh is intelligent enough to know they can’t eat celestials though and they only slay such creatures and dump their corpses somewhere else.
Otyughs themselves are living heaps of diseases and sickness, spreading the worst of them among prey that got away after being bitten or touched by their two tentacles, some escaped victims of the Otyugh has caused entire villages to die on plagues or pest.
Otyughs thrive in sewer-systems and refusal heaps on earth or also on other planes, though the Abyss seriously changes the Otyughs appearance, their flesh becomes green and it turns into a living hive for all types of hellish vermin that use its sick flesh as shelter to breed and worse, the pain these vermin cause to the oytugh makes it extremely hostile and grumpy to anything it spots. Abyssal Otyugh are known as Draudnu’s and when another creature looks at a Draudnu for too long they get sick feelings about monstrous worms or parasites that burrow through their flesh and which live inside them, in the worst cases the victims even cut out their own intestines to get rid of their imaginary parasites.
On Earth Otyughs are often imprisoned by Orcs, Goblins or other evil humanoid races to be used a living disposal system, unworthy slaves are sometimes sacrificed to the Otyugh but they are mostly fed with the Orc’s and Goblins filth, dead and the sick.
Otyugh tolerate all types of Green Slimes and Carrion Crawlers in their territories, but even such creatures aren’t always safe from their eternal hunger for filth. Black Puddings however hunt for Otyugh’s and are their main predators.