Gribald Perfect Accomplice

As Gribald Perfect Accomplice comes into play,
you may choose a creature in play. If you do,
Gribald comes into play as a copy of that creature, except its name is still Gribald Perfect Accomplice.
Whenever a non-token creature enters the battlefield, you may create a token copy of it if you
pay {3}{u}{u}.
Creatures you control are non-legendary.