Khal Drogo

Trample, haste
Whenever Khal Drogo attacks, put a creature card from your hand with power less than Khal Drogo's power onto the battlefield tapped and attacking. At the end of combat, you may pay that creature's mana cost. If you don't, sacrifice it.
Whenever you sacrifice a creature, put a +1/+1 counter on Khal Drogo.