Minotaur

A minotaur is a half-man, half-bull. Unfortunately for the woman giving birth to the thing, the head is taurine, giving the monster huge horns.

This creature originates in Greek mythology, which is pretty fucked up. The first minotaur was born to Pasiphae, the wife of a king of Crete named Minos. She had taken a fancy to a white bull that the king liked more than her. Apparently, she liked the bull more than she liked the king as well. After the minotaur was born, it was kept in a labyrinth so that ordinary people wouldn't have to look at it. This might seem like a pretty raw deal for the minotaur, but on the other hand the Cretans sacrificed virgins to it every year.

As a result of this story, minotaurs are associated with labyrinths and mazes of all kinds. For example, in 4e they enjoy puzzles and feel at home in twisting, turning passages. Whenever minotaurs build towns or cities, the roads are always arranged in the most confusing way possible. To the locals, this makes perfect sense. To adventurers, it's a fucking pain. To GMs, it's an easy way to take up an hour or two of the party's time after they breeze through your perfectly designed challenge in 5 minutes and you have nothing left this session.