Blood Magic

Through occult research and unearthing of infernal knowledge, the creature becomes capable of spending its life force instead of spell slots to cast spells.

The caster can expend hit points to cast a spell of 5th level or lower. For every level of the spell the caster loses 2d12 hit points. The caster can use this feature once per Short Rest. Additionally, the caster gains access to a ritual dagger. This dagger counts as a magical weapon as long as it is wielded by them. However, the dagger never registers as a magical object for spells like detect magic.