Renekton, Desert Butcher

Trample, Haste
Landfall - Whenever a land enters the battlefield
under your control, exile the top card of each
players library, Renekton, Desert Butcher gets
+X/+0 until end of turn, where X is equal to the highest mana value among the exiled cards.
Whenever Renekton, Desert Butcher attacks, you
may put a land card, exiled with Renektons ability,
onto the battlefield under your control