Redok the defiler

Annihilator 5
When you cast Redok the defiler all lands your opponent(s) controls become wastes and lose all abilities. When Redok the defiler leaves the battlefield exile all cards in target players graveyard then during then end of that players next turn place Eldrazi scion tokens onto his or her battlefield equal to the number of cards exiled with this ability.
All wastes gain {c}{t}add {c}{c}{c}{c} to your mana pool