Garviel Loken was originally the Captain of the Luna Wolves (later Sons of Horus) Space Marine Legion's 10th Company during the last days of the Great Crusade and up until the Istvaan III Atrocity that initiated the Horus Heresy.
Loken was highly regarded as a warrior and commander by both his brethren and his primarch. Admired for his cool head and intelligence as well as his record in battle, he was given the honour of induction into the Mournival, his Legion's cadre of close advisers to their Primarch Horus. However, after Horus' fall to Chaos on Davin, he was considered too loyal to the old ways -- the ideals of the Great Crusade and the Emperor, to be inducted into the dark conspiracy that was overtaking his beloved Legion.

