Ohlsana, the Shadow Mother is an ancient being of power originally imprisoned in the Shadow Plane by Severn, the Manipulator, who remains Her jailer to this day. Her current prison is of Lanos' make, who sacrificed much of His original essence to drive Her back into the Shadow Plane. The weakened foundations of Her prison allow Her to channel a fraction of Her immense power through the cracks. Those touched by this power are known as the Shadowbound.
Pre-Midnight Age
Very little is known about Ohlsana before the Midnight Age. Her imprisonment upon the plane of Shadow began long before the modern era. She is mentioned in several ancient texts of Albedian origin - although the scholars and priests of Delve refuse to talk about Her - that indicate the Shadow Mother is an Albedian God.
Ati, a creature long thought to be a deity of corruption and shadow by the Rajamala, is in fact a demigod originally birthed by the Shadow Mother in the days of old. Long bound to the Itzatl after losing its corporeal form, its current whereabouts are unknown now that it has achieved a physical presence.
Midnight Age
The first time the Shadow Mother's presence was felt in the Midnight Age was during the 60th year. Severn, the Manipulator struck a deal with Ohlsana, offering Her freedom in exchange for Her cedeing dominion over the shadow beasts to Him, as well as killing His brother, Lanos.
Ohlsana descended upon the continent of Sapience and unleashed Her shadow beasts upon its populace. While the mortals battled Her minions, Lanos, the Lord of Truth, rose to battle the Shadow Mother. Wielding the swords of Truth and Justice, He struck Ohlsana blow after blow, driving Her back through the rift which led to the Shadow Plane.
Within Her own domain, the Shadow Mother easily overpowered the Lord of Truth. In His dying moments, Lanos spent the last remnants of His essence to strike Ohlsana a grievous wound, and sealed Her once more within a makeshift prison of His own construction. Over time, parts of the essence forming the prison have dissipated, eventually forming into the God Damariel. These cracks in the foundation of Her prison has allowed Ohlsana to channel Her immense power through them to exert Her influence upon the outside world once more.