Comic Nexadded February 28, 2020

Hey there comic fans! #FirstAppearanceFridaytime! This week it's Beta Ray Bill! He first appeared in The Mighty Thor #337and was created by Walt Simonson.
Beta Ray Bill started life as an adversary to Thor fighting him as his ship Skuttlebutt travelled towards Earth. Taking advantage of Mjolnirs enchantment that reverts Thor to his secret identity when seperates from Thor for too long. He defeats Thor and takes up Mjolnir for himself, thus being granted all the powers of Thor.
After a battle with SHIELD when landing on Earth, Beta Ray Bill is transported to Asgard. Where Odin seeing Bill can wield Mjolnir calls for Thor and Bill to fight to the death! After knocking each other out Bill renounces his claim to Mjolnir and seeing how worthy Bill is Odin has Eitri forge a new hammer: Stormbreaker and transfers the enchantment that returns Thor to his human form from Mjolnir to Stormbreaker allowing Bill to return to his original form
And after learning of a common foe in Surtur Beta Ray Bill joins th Asgardians as an ally.
Beta Ray Bill is a hybrid cyborg equine like creature but this is not his original body, his consciousness was transferred into this body by scientists from his original race. This body gives him superhuman, strength agility, endurance and durability. Bill is also a skill hand to hand combatant, beating even Thor.
Then of course with Stormbreaker he is afford all of the additional powers of being Thor.
The Mighty Thor #337- first appearance
The Mighty Thor #337-340- origin story
Stormbreaker: The Saga of Beta Ray Bill
Beta Ray Bill: Godhunter