3. Galactus the Devourer of Worlds
It is hard to say whether or not Galactus is actually evil. In a lot of ways he is beyond good and evil. He is a god-like cosmic entity who must consume planets with potential to support life in order to sustain his own life. Even though millions of lives and entire civilisations have been destroyed by Galactus, he must live and continue to consume as he is an essential part of the cosmic order of the universe. Galactus wields the Powers Cosmic which allow him to produce almost any effect that he desires, including size-alteration, transmutation, telekinesis, teleportation (including teleportation of entire galaxies), creation of force fields and interdimensional portals, creation of sentient life and recreation of the dead (including entire worlds). He can bestow others with a small fraction of the Powers Cosmic, which he does to create his heralds. The contemplative Silver Surfer is one of those heralds. His great powers do however come at a cost. He must consume planets in order to maintain his energy. The heroes of earth have on a number of occasions been able to resist Galactus when he is low on energy. Galactus appeared in the 2007 film Fantastic Four: Rise of the Silver Surfer as a cloud formation rather than the classic giant purple humanoid with a tuning fork head. He also seemed to have reduced powers in that he was easily defeated by his own herald the Silver Surfer.
Likelihood of appearing again Due to Fox already using Galactus and the Silver Surfer in film, they own the rights to use them in future films. Apparently there were some discussions between Fox and Marvel Studios about giving Marvel the rights to use Galactus and the Silver Surfer in exchange for extended film rights for Daredevil. The film rights for Daredevil have since reverted to Marvel, so it is unlikely that Galactus and the Silver Surfer will be in the Marvel Cinematic Universe anytime soon. Fox however are currently working on a Fantastic Four reboot. Galactus and the Silver Surfer are likely to return in the reboot, maybe not in the first film but quite probably in a sequel.