Saimink, Shadowy Slime

Saimink's power is equal to your devotion to
black.
Whenever another creature deals damage to
Saimink, you may pay {4}. If you do, put a -1/-1
counter on Saimink and gain control of that
creature until Saimink leaves the battlefield.
{1}{w/b}{g}{u}, {t}: Put a +1/+1 counter on Saimink,
then she fights another target creature.