You can use your action three times in a row to bind the soul of a dead creature, transforming it into a shadow, which can be summoned in combat with Shadow Release as an action. Every turn you have to roll 1d20.and at least two results have to be 10 or higher to successfully bind the creatures soul.
If you roll three times a 10 or higher, the shadow has the original size of the creatur with the Hitpoints it had living.
If you roll two times a 10 or higher, its Hitpoints are halfed and the size of the shadow is smaller based on the creatures original size (except for tiny, small and medium creatures):
- Large (up to 10 ft.): two thirds of the original size
- Huge (10 ft.-15 ft.): half of the original size
- Gargantuan (15 ft. or larger): one third of its original size