Venom is a recurring character in Marvel's Spider-Man series. It is a symbiote who bonded with a host’s body.
It briefly appears in the endings of both the first game (post-credits) and Miles Morales (mid-credits), where its first host reveals to be Harry Osborn. It will have a role in the second game/third installment.
Sometime after Harry Osborn's needed treatment for his Oshtoran Syndrome, a black substance, presumed to be Venom, clings to his body inside a stasis until a cure for Harry's condition is found.
Marvel's Spider-Man: Miles Morales
While a black substance which is presumably Venom still attach to Harry in after the end of the game, off-screen, Curt Connors is enlisted by Norman to examines and studies the young Osborn's disease, and the substance which kept him alive. Just as Harry wakes up hearing the news of Rio Morales becoming New York City Council since the fall of Roxxon and Underground, Norman becomes impatient of seeing his son remains in the container long enough, and orders Curt to get him out, despite the doctor's warning.
Marvel's Spider-Man 2
Venom is a black shape-shifting substance when not hosting a body. However, when it does, Venom develops traits that match its host, usually including a muscular humanoid form, a mouth with long sharp teeth, and large, blank-white eyes.
Powers and abilities
Venom appears as a substance that possesses the ability to host the bodies of other living creatures. While being bonded to Harry Osborn, the symbiote keeps Harry's Oshtoran Syndrome in check.
The Symbiote first appeared as Spider-Man's alien costume in The Amazing Spider-Man #252 in May of 1984, with the circumstances behind the costume change revealed in the December, 1984 issue of Marvel Super Heroes Secret Wars.
It would later appear as Venom in The Amazing Spider-Man #299 in April of 1988.