The Petrova Line

Whenever a player taps a land for mana, that player adds two mana of any type that land produced. Then put a Consumption counter on that land, and The Petrova Line deals damage equal to the number of Consumption counters on that land to that player. Pay half of your life, rounded up: Destroy The Petrova Line. It can’t be regenerated. Any player may activate this ability but only during their end step.