Magzok, the Worlds Bane

When Magzok, the Worlds Bane enters the battlefield all opponents pick 2 lands he or she controls then all the others become waste lands and can only produce colorless mana.
for as long as you control Magzok, the Worlds Bane all opponents lands untap every other turn.
When Magzok, the Worlds Bane deals combat damage to a player gain control of target land that player controls.