The Soul Stone

Infinity stone
Whenever The Soul Stone enters the battlefield,
exile it unless you exile an untapped legendary creature other than your commander.
{p/b}{t}Destroy target creature or planeswalker.
{5}{p/b}{p/b}{t}Return to the battlefield all creatures
from all graveyards under your control,
The Soul Stone doesn't untap during your
next untap step.
"In order to take the stone, you must
lose that which you love. A soul for a soul."