Vorn, the Berserker

Haste, Trample
When Vorn, the Berserker enters the battlefield,
untap all creatures that attacked this turn. After
this phase, there is an additional combat phase
followed by an additional main phase. You may
cast Vorn the Berserker only on your turn.
His foes expect a hulking visage such as Vorn to
deliver blows of great punishment. What they don't
expect is for him to do it so fast.