In The Neverhood the player does not know very much about Klaymen other than the fact that he is the games main character. The player leads him around in a traditional point & click style as he begins his journey to save the neverhood. Klaymen stores any items he has in a hidden compartment on his belly that he opens by pressing the button furthest to the right on his chest. Klaymen seems to be invincible as he has the incredible ability to regrow parts of himself. e.g when his head is chopped off by a crab like creature he simply regrows it and can continue unharmed.
As you may be able to depict, Klaymen is made out of clay. He wears a red shirt with three buttons. He has a dull colored body and walks very clumsily.
Throughout the game, starting when he first wakes up in a room, it is apparent he does not know very much about himself, and he does not speak, even when he starts meeting his friend, Willie Trombone. He does scream and make sounds in the many comedic claymation cutscenes in the game, but he does not speak until the end, when you speak with Hoborg.
Here, Klaymen is also the main character. During the game, Klaymen has already learned alot about himself and is trying to find his way through the planet Idznak, which is full of dimwitted creatures called SkullMonkeys. The game was not a point and click adventure like Neverhood, and Klaymen found himself traveling in a manner to those in Donkey Kong Country.