Wurm Raiders of the Plains

Creatures cannot attack you unless their owner's
pay {2} for each attacking creature.
{4}{r}{g}, {t}: Create a 5/5 Red and Green
Legendary Wurm creature token named "The Plainscape Devourer," with "This creature gets
+3/+3 and gains trample if a creature hasn't
attacked you since your last turn." (This activated ability is also considered casting a spell. This creature
token is also considered your Commander.)