Obuun, Mul Daya Ancestor [Commander: Zendikar Rising]

At the beginning of combat on your turn, up to one target land you control becomes an X/X Elemental creature with trample and haste until end of turn, where X is Obuun's power. It's still a land.
Landfall — Whenever land enters the battlefield under your control, put a +1/+1 counter on target creature.