Severed

Flying
{1}{b}, {t}: Rather than pay the mana cost of the
next spell you cast this turn, you may pay life
equal to that spell's mana value.
"A sentient lifeform named as 'the Severed' in the
Xeno-type writings. They share a physiological similarity to the "normal" sentients, so presumably
these individuals are the result of [UNDEFINED
ERROR]."