He was confirmed as a major threat almost immediately in his introductory arc when he defeated Spider-man with ease and the fact it took both Peter and Venom working together to overcome him. I place that 3 issue arc over Maximum Carnage in terms of importance because, without it, a lot of things simply wouldn't have happened (which Mister Mets summed up in his in his initial post).
I'll have to take your word for that. But was Maximum Carnage ever in danger of being a dud? It had Spider-man, Venom, it was Carnages second return appearance, was 14 issues in length, and featured a multitude of guest heroes.Fact is, in hard sales terms, this was Marvel's biggest ever event until CIVIL WAR, i.e. it was the biggest event storyline of the '90s. Bigger than Age of Apocalypse, bigger than Heroes Reborn, bigger than what-have-you.