The Other Schnee (RWBY X EVIL!OC)

Wren Schnee, the sadistic twin brother of Weiss, was locked away at seven years old after massacring 300 Faunus in the Schnee Dust Mines and using their bodies for twisted experiments. Hidden from the world in the maximum-security prison Tartarus, Wren's monstrous genius festered in isolation.

Now, ten years later, Ozpin makes a daring move-releasing Wren to attend Beacon Academy, hoping to turn his darkness against Salem. But Wren has his own agenda, and his presence threatens to unravel Weiss's fragile new life. As allies question his redemption and enemies fear his cunning, Wren's actions could either save Remnant-or destroy it.