When The Mud Pack disbanded, Sondra Fuller and the third Clayface, Preston Payne, fell in love and had a child who they named Cassius. He was kidnapped by Abattoir, who forced the boy's parents back into villainy.
He was seperated again from his parents and held in a government laboratory. The scientists were working on finding the extent of his powers. If a piece was seperated, it could grow a mind of its own but can only think in unstable thoughts that it receives from Cassius. A piece bonded to a person becomes Claything, a being with the abilities of typical Clayfaces, as well as Preston's ability to melt objects. Cassius can only stay in his clay-like appearance for a certain time.