Marvel Heroes

Marvel Heroes is a free to play massively multiplayer online game by Gazillion Entertainment.

About
Marvel Heroes was a free-to-play MMO Action RPG created by David Brevik, the visionary behind Diablo and a team of industry veterans assembled specifically for this project. Marvel Heroes combines core gameplay elements of Diablo with the expansive library of characters from the Marvel Universe.

Features
The official site describes the following features:

Marvel Heroes combines core gameplay elements of Diablo with the expansive library of heroes from the Marvel Universe, including all your favorite Marvel Universe.
 * Engage in Action-RPG-style gameplay, but in an MMO world.
 * Team up with your friends, or play solo.
 * Randomly generated environments are different every time you play.

Collect and play as your favorite Marvel Super Heroes including Iron Man, Thor, Black Widow, Captain America, Wolverine, Hulk and many others.
 * Choose from a list of fan favorites from the Avengers, X-Men, Fantastic Four, and every corner of the Marvel Universe.
 * Build your character using a library of spectacular powers appropriate to your hero.
 * Customize your character with a library of costumes from Marvel's rich history.
 * Discover an endless variety of gear to increase your hero or heroine's power.

Explore the Marvel Universe in a story crafted by comic book super-scribe Brian Michael Bendis.
 * Visit famous locations from the Marvel Universe, from Avengers Tower to Mutant Town to the Savage Land.
 * Smash through hordes of iconic Marvel enemies, such as the dreaded Purifiers and the legions of HYDRA.
 * Face off against dozens of super-villains.

Trivia

 * There are no current trivia available on this topic, as of the moment.