The au is called possessed (open to different ideas!) In this tigerclaw, K!lls ravenpaw, and this leads firepaw to kill him Tigerclaw, in the dark forest, discovers he can possess Firepaw. At first, he just makes his life miserable, but after around a month, he decides to live his life in Firepaw! (When possessed, Firepaw's eyes are brown, not green)
