Riley, Diregraf Prototyp

Riley, Diregraf Prototyp enters the battlefield
with a +1/+1 counter on it for each Necron card
in your graveyard.
Whenever you pay one or more life, Riley,
Diregraf Prototyp deals that much damage to
target creature.
Whenever a creature an opponent controls dies,
put a +1/+1 counter on Riley, Diregraf Prototyp.