Stonebrow was Kamahl's right hand after the death of the centaur elder Seton at the hands of the dementia summoner Braids. When Kamahl used the Mirari to amplify the creatures of the Krosan Forest, Stonebrow served as the general of the strange army. The axe he carries is Soul Reaper, the same axe Kamahl used to cleave Phage and Akroma in a single blow, thus creating the false god Karona.
Moments after a fickle rift dropped Stonebrow in the waste of his beloved Krosa, he took up his axe in rage-blind vengeance. (Stonebrow)