Scaila, Effigy of the Saklari

Endure (whenever another creature you control dies put a +1/+1 counter on this creature)
Whenever a Naga enters the battlefield under your control put a +1/+1 counter on Scaila.
Remove three +1/+1 coutners from Scaila: Put a -1/-1 counter on target creature, gain 2 life.