He who Ruled Them All

Vigilance, Menace
Rats you control are indestructible during your
turn.
Whenever a rat you control dies, put a +1/+1
counter on all rats you control, you become the Monarch. Can only be activated once per turn.(Monarch: At the beginning of your end step, draw
a card. Whenever a creature deals combat damage
to you, its controller becomes the monarch.)