Alpharius

Alpharius Omegon is the Twin Primarch of the Alpha Legion. He is unique amongst his brothers, as he is one soul split between two identical bodies. His true nature, childhood, and even his homeworld is a closely guarded secret.
 * In the baseline Lovehammer universe, Alpharius Omegon and the rest of the Alpha Legion split between Traitors and Loyalists, with Omegon assuming the identity of Alpharius and leading a bloody vendetta against Serenity.  Alpharius, having taken the name of Omegon, currently leads the loyalists in a shadow war against Omegon.