Tigrex, the Roaring Wyvern

Haste, Trample, Exert
Whenever Tigrex, the Roaring Wyvern is Exerted, untap Tigrex, the Roaring Wyvern and there is an additional combat phase this turn. Tigrex deals 1 damage to itself.
Its bark is just as deadly as its bite
-Pokke Hunter