From mutant-killing robots to tyrannical aliens, these are the most powerful X-Men villains who aren’t mutants.

The X-Men are one of Marvel's original teams, and throughout the years, they have been in some of the company's best stories.

When it comes to science fiction, there are numerous styles and flavors to choose from. That's what makes the genre so fun.

From the comic's description, we can infer that this new series will be set during season 2, when Aang and Team Avatar are ...