Book of Shadows: Velsharoon's grasp of organ

The caster creates a magical force that grips the subject's heart (or similar vital organ) and begins crushing it. The victim is paralyzed (as if having a heart attack) and takes 1d4 points of force damage per round. Each round, the caster must concentrate to maintain the spell until the victim succeeds on a wisdom saving throw ending the spell or they are dead. In addition, a conscious victim gains a new saving throw each round to stop the spell. If the victim dies as a result of this spell, his chest ruptures and bursts, and his smoking heart appears in the caster’s hand.

This spell only affects living creatures with identifiable organs (example Oozes our not affected).