Doknar Mountainflaw

Doknar Mountainflaw can be cast for
{1}{p/g}{p/g}{p/r}{p/r} instead of paying its mana cost.
You may only reveal Doknar Mountainflaw if 3
or more lands have entered the battlefield this
turn. After Doknar Mountainflaw has been
revealed you may cast him on your turn.
(the cmc of this card is 3)
Mountainwalk.
Whenever Doknar Mountainflaw deals combat
damage to an opponent populate.