Annihilus

Just like Mad Jim Jaspers, Annihilus would be a great one-time villain to be included in the Marvel Cinematic Universe. Whether he clashes with a single hero (or the Guardians of the Galaxy), whether he goes against the Avengers themselves, the lord of the Negative Zone would be a great addition "“ if he wasn't owned by Fox, of course.

While he is in the comics a traditional adversary of the Fantastic Four, with his Cosmic Control Rod he was able to defeat even the mighty Thor in combat. The fact that he is basically immortal (since he is reborn each time he dies) makes him even more powerful.

And so if the Marvel Cinematic Universe will expand throughout the universe and beyond, maybe a Negative-Zone-like dimension could be found. And, say, Captain Marvel, or the Guardians of the Galaxy, or some-other cosmic superhero (even Doctor Strange) will discover an Annihilus-like supervillain.

It could work, right?