March of the Penguins

At the beginning of your upkeep, create a 1/3 blue and white Bird creature token named Penguin with "This creature can't gain flying."
March -- At the beginning of your upkeep, if you control three or more other creatures that share a creature type with this permanent, tap target permanent without flying. It doesn't untap during its controller's next untap step.
They may look cute, but don't get in their way...