Drain Power

The teeth of this design once pointed back at the caster. In its original rules engine, forcing an opponent to tap out every land and routing the resulting pool to you stripped away their ability to interact on your turn: they had no untapped mana to respond with until their own untap step. But the spoils carried a catch the target never had to worry about. The stolen mana entered your pool, which meant you were the one at risk of mana burn if you could not spend it before the step ended. The opponent lost the mana but never the life. That tension is what made the card legible: a sudden mountain of colored mana you had to actually use, lest your own greed scorch you.

The revisions since have hollowed it out from both directions. Mana burn is gone, so the dangerous half of the bargain no longer exists; what remains is a sorcery that hands you whatever an opponent left untapped and accomplishes nothing against a board already empty. Its payoff is a function of the target's lands, not your own resources, which makes it swingy in a way disciplined rituals never are. Mana Drain later found the cleaner synthesis of mana-theft design, stealing on a counterspell's terms. Drain Power is what mana theft looked like before the system that justified it was dismantled.