Amumu, The Sad Mummy

When Amumu enters the battlefield, curse target opponent. When Amumu leaves the battlefield, remove the curse.
Whenever an opponent attacks, you may tap up to 3 creatures cursed player controls.
{1}{u}{t}: Attacking creatures your opponents control that attack you get -2/-1 until end of turn.
{u}: Amumu may block an additional creature this combat.