Venom
Venom is a fictional character appearing in American comic books published by Marvel Comics, commonly in association with Spider-Man. The character is a sentient alien Symbiote with an amorphous, liquid-like form, who survives by bonding with a host, usually human. This dual-life form receives enhanced powers and usually refers to itself as "Venom". The Symbiote was originally introduced as a living alien costume in The Amazing Spider-Man #252 (May 1984), with a full first appearance as Venom in The Amazing Spider-Man #300 (May 1988).
