Olpy, the Silliest Goose

Hexproof

Whenever Olpy, the Silliest Goose enters the battlefield or attacks, create a Silly Guy token. (It's
an artifact with "{b}, {t}, Sacrifice this artifact: At the beginning of your next upkeep, create a 1/1 black Silly Zombie Guy creature token.")

Zombies you control get +1/+1 get for each Silly Zombie Guy you control.