Wei, Anti-Mage's Disciple

Haste
Mana Break—Whenever Wei deals combat
damage to a player, tap that many target lands
that player controls.
{4}, {t}:Mana Void—Wei deals X damage to target
player, where X is the number of tapped lands
that player controls.
"He was younger, full of fire. Looking for a fight.
Not a child..."
—Wei