Beta Ray Bill is a cyborg Korbinite alien who rescued his people from their galaxy after it was destroyed by Surtur. Eventually Bill came into conflict with Thor but proved himself worthy of wielding Thor's Hammer Mjolnir. This lead Thor's father Odin to question whether Bill or Thor should be his heir so he manipulated the two into fighting with Bill defeating Thor several times only for Thor to emerge victor at the end. Ultimately, Beta Ray Bill was given his own Mjolnir-like weapon to him called Stormbreaker and he became a superhero.
This character is exclusive to the DLC Super Pack, which is received by pre-ordering or purchasing the DLC on Xbox 360 or PlayStation 3 and Steam.