Claymates

From the creators of Clay Fighter comes a game about a shape-shifting ball of clay. You play as a boy named Clayton, whose father has developed a serum to turn humans into animals. However, an evil shaman desires this serum, and when he is denied ownership of it, he kidnaps Clayton's father and turns Clayton into a ball of clay. It's up to the unlikely hero to rescue his father, the serum, and the world! The game is a side-scrolling platformer. (mobygames.com)