When using the Shift 5 ability, which allows the six-cost card to be played one turn early if a cheaper Merlin can be commandeered for the cause, Merlin gets to make use of another feature called Overdeveloped Brain
This often takes the form of removal, like Thraben Charm and Will of the Mardu, though some cards buff creatures based on how many you control, like Heidegger, Shinra Executive and Team Avatar
Collect and assemble all 9 to create a cool artwork
The point is to make Gandalf huge and swing with him, and it doesn't really matter how
When the last is removed, sacrifice it.) When Crack in Time enters the battlefield and at the beginning of your precombat main phase, exile target creature an opponent controls until Crack in Time leaves the battlefield