With its latest game update (2.15), Gazillion Entertainment has added the well know X-Men character, Nightcrawler to the list of playable characters in their free-to-play, superhero MMO Marvel Heroes. This brings the list of playable superheroes to twenty nine.
The game is free-to-play, with the option to purchase "Hero Packs" through the in-game store if you don't want to spend the time unlocking them in-game, and features all sorts of well known Marvel superheroes and villains, including Wolverine, Captain America, Spider-Man, Iron Man, Thor and a whole bunch more. Players can also choose various costumes from over seventy years of Marvel history.
You can check out the game at the source link if you think it sounds like fun.