This character is an alien Thor and he met in an incident in which he thought Thor was one of the characters that attacked him, during the fight he managed to lift Thor's hammer showing himself to be one of those worthy of that power, that was at the time in that Thor had a time limit to be without the hammer or he would be mortal Donald Blake again. But then when he attacked with Thor's hammer, Odin made him appear in Asgard trying to summon Thor, and then he stopped him during the attack and managed to summon Thor, the whole situation was explained and Thor recovered the hammer, being revealed that Bill he was attacking the creatures that were the emergency Odin called Thor from. And for Bill to enter the fight he won his equivalent to Thor's hammer a new one was made (which looks more like a hammer because Thor's technically is shaped like a sledgehammer) he also got an armor similar to Thor's. The character is described as being as strong and tough as Thor, and just as Thor's hammer turned into a cane at the time when he became Donald Blake, Bill could make the armor disappear and make his hammer become a cane too.
In other media 
Edit
The cartoon "Avengers: The Mightiest Heroes of Earth", as he didn’t use Donald Blake’s storyline, made some changes like Bill couldn’t make his hammer go nowhere or his armor disappear, the Super Hero Squad Show cartoon that also does not use the storyline Donald Blake did the same thing.
