Brony

: Brony enters the battlefield with loyalty counters equal to the number of ponies, unicorns, pegasi, and alicorn creatures on the battlefield.
+2: Target creature gains +1/+1 and "this creature can't be blocked by creatures shown outside" until end of turn.
-3: Place 3 sticky counters on up to 3 target creatures. Then, if a creature has 3 or more sticky counters on it, exile it.