Source: i09.com

9. Infestation

Included Titles: Infestation # 1-2, Infestation: Transformers # 1-2, Infestation: Star Trek # 1-2, Infestation: Ghostbusters # 1-2, and Infestation: G.I. Joe # 1-2

A rare non-Marvel or DC crossover on this list, Infestation is a very fun time.

It's like the perfect Halloween comic event. In the opening chapter, some scientists unleash a horde of zombies across the multiverse. And those zombies flowed out across several of IDW's licensed property comics. Those being the crew of the U.S.S. Enterprise, the Autobots, the G.I. Joe squad, and the Ghostbusters. And they're all pretty fun. Star Trek is probably the highlight, with a wry sense of humor about the whole silly concept.

The universes don't cross over, but that's not what this is about. It's just about pitting some of our favorite characters against some fun Halloween zombies.

Long-term effects: I mean, this was sort of nebulously out of continuity for most of these comics. But the transformers one had some effects! It sent Kup to the netherworld for like three years. So that's a thing.