Zoo Escapees Foil

Creature — Boar Rhino

When this creature leaves the battlefield, create a Mutagen token. (It's an artifact with ", , Sacrifice this token: Put a +1/+1 counter on target creature. Activate only as a sorcery.")

They imagine that out beyond the zoo, beyond the pen, there exists another world, and it encroaches with rapid certainty upon their own . . .