Whiplash Goblin

{t}: Whiplash Goblin deals 1 damage to target creature or player.
Whenever a creature or an artifact enters the battlefield under an opponent's control, untap Whiplash Goblin.
"When a problem comes along, you must whip it!
Try to detect it, it's not too late,
To whip it! Whip it good!"
-- Goblin marching song