10 Most Powerful Beings Venom Has Defeated
2. Superman - DC/Marvel: All Access
DC and Marvel, though they would probably find the idea repulsive these days, have crossed over multiple times throughout both company's history. One of their lesser known crossover events is DC/Marvel: All Access. It is in this story that Superman, the Man of Steel, the mightiest superhero of them all, suffered probably one of his most humiliating losses at the hands of everyone's favorite symbiote.
The questions begin when Venom, a guy who can't even get rid of one teenager in a red and blue onesie, no-sells a right hook from Superman, and then responds by knocking Superman on his ass and damn near choking him to death with his symbiote goop.
The fact that this fight is so short, and NOT for the reasons of "Superman punched Venom into space", is head scratching all on its own, but why the writers didn't take this opportunity to show us what a Superman controlled by the Venom symbiote would look like goes to show why this crossover isn't very fondly remembered.
But hey, you defeated Superman, Venom! Bully for you!