You choose the player, planeswalker, or battle the creature you put onto the battlefield is attacking
Once you reach max speed, you can tap him to create red mana equal to the number of Goblins you control , which can get absurd quickly in conjunction with how many Goblins red players like to put on the battlefield
Fathomless descent Each creature card in your graveyard perpetually gets +X/+X, where X is the number of permanent cards in your graveyard
By itself, Merlin, Goat is a useful way to gain an extra couple of lore for its four-ink cost - and deter your opponents from getting rid of him, as they take you one step closer to winning
You could tack that damage onto an Abraded Bluffs and send it to face, or you could modulate the damage a burn spells going to do to line it up with an opposing threats toughness and draw a card