In the early to mid-90s it seemed like everything with Spider-man also featured an alien symbiote. Said symbiote first bonded with Peter's Spider-man suit, augmenting his abilities, but also bringing out his darker side.
Sam Raimi's version of a "darker" Peter
After Peter separated himself from the symbiote, it latched on to Eddie Brock. Their combined identity became Venom. Then the symbiote reproduced asexually because, you know, symbiotes gonna do what symbiotes are gonna do. The new entity bonded with Cletus Kasady, turning him into Carnage.
Then a bunch of stuff happened, culminating in the Maximum Carnage comic event. A game was made for the Genesis and SNES to tie in with the event. Today, I look at that game to see if it is as fun as I remember it being.