GLaDOS' Tower

Pay 2 life: Tap GLaDOS' Tower. Put a 4/4 white and red Human creature token onto the battlefield. It has "At the beginning of each opponent's upkeep, if this creature is tapped, that player gains control of it."
Whenever GLaDOS' Tower becomes tapped, put a 1/2 blue Human Wizard creature token onto the battlefield. It has "Whenever this creature blocks, it deals 3 damage to target creature it is blocking."