The Wug are a race of nasty, brutish humanoid frogs. They infest swamps and other waterways, regularly attacking other humanoids in search of loot and sacrifices. A wug resembles a bipedal frog with a wide mouth, bulging eyes, and splotchy green skin. An adult stands around 5 feet tall and weighs around 180 pounds; males and females are roughly the same size, and non-wugs cannot generally tell them apart. A wug generally goes about naked except for a belt to carry its knives and pouches. Wugs speak Common and their own croaking tongue.

A wug is a crafty and merciless warrior, throwing itself into battle with a zealous fanaticism. It will attempt to take prisoners when possible for later sacrifice. It prefers to attack from ambush and is cunning enough to use the terrain to its advantage.

Wugs are known to tame other amphibious monsters, in particular giant frogs and toads as well as prince frogs; such creatures might be encountered in a wug lair.