FROM MTV GEEK: In true Marvel fashion, the end credits of "Avengers" lead to an extra scene. And while most of the audience was insanely confused by the creature—one person next to us even asked if it was Hellboy, we kid you not—the true comic book fans gasped in recognition of the villain.
Thanos began as an answer to DC Comics' Darkseid, but evolved into one of the Marvel Universe's most important characters. He hails from Saturn's moon, Titan, and genetically altered himself to be extra strong and super smart. So how does he relate to "Avengers"? The bad guy clashed with lots of Earth's mightiest heroes as he searched for the Cosmic Cube on Earth, also known as the Tesseract—gasp! Other interesting facts: Thanos is in love with Death (a lady skeleton) and doesn't deem himself worthy to win any battles.
Head to MTV Geek to find out more about Thanos and his big-screen involvement!