Makeshift Army

Makeshift Army enters the battlefield with X
+1/+1 counters on it, where X is the number of Squirrels under your control.
Whenever an opponent is dealt damage, put a
+1/+1 counter on Makeshift Army.
"Their ranks? Thin. Their formation? Improvised. We
can easily defeat them! What's that sound?"
- General Cragrock, last words