Sandman (William Baker a.k.a. Flint Marko) has the ability to transform his body. He can will his body hardened, compacted, dispersed or shaped, or a combination of those qualities, an Earth manipulation of sand and rock particles. More often than not in combat, this ability enables him to absorb most blows with little to no ill effect other than reforming himself, a relatively fast action. His striped shirt and cargo pants are colored sand to make him appear as if he wears clothes. Even when soaked, he was able to stretch his sand molecules, growing to double his size.
Sandman can mold his arms and hands into shapes such as a mace or a sledgehammer to battle Spider-Man and his other enemies. His mass, strength and shape shifting ability correspond to the number of sand and rock particles that comprise him. The more he incorporates (nearby) sand grains and rock granules into his body, the more those qualities are enhanced. Even though he controls every particle in his body, his mind exists in the astral plane. He can turn himself into a sandstorm, which enables him to fly great distances and to suffocate his enemies. (Wikipedia)