Gut Nibbler IV, the Rat-King

As long as you control more than ten Rats, Gut Nibbler IV, the Rat-King is indestructible.
Whenever a Rat creature enters the battlefield
under your control, put that many 1/1 black Rat
creature token onto the battlefield.
{b}{b}{b}, {t}: Put a +1/+1 counter on target Rat creature. It gains deathtouch until end of
turn.