One of the Draumar, servants of the Serpent, Bonegrinder has served the Serpent for millennia, originally present when Odin led his original assault on the Serpent's citadel, a battle that led to Bonegrinder's death.
Consigned to the afterlife, Bonegrinder and the rest of the Draumar arose in the modern day following the Serpent's release from his prison. Assaulting Hel and destroying the deceased Asgardians present, the Draumar were briefly halted by the arrival of Dani Moonstar, briefly granted Valkyrie powers by Hela. Consuming Moonstar, Bonegrinder continued his assault on the denizens of Hel until Moonstar's teammates, the New Mutants arrived, seeking to aid her. Hearing her teammates, Moonstar escaped Bonegrinder's stomach, tearing through his flesh, but only momentarily injuring him. Though he soon began to assault the New Mutants, their combined powers proved enough to defeat him.