Lavaball Trap

Catch an opponent flooding their own manabase, two or more lands hitting the battlefield on the same turn, and the eight in the corner drops to : an instant-speed blowout that wipes two lands and torches every creature with four or fewer toughness. That conditional is the entire transaction. A ramp deck untapping a double-land sequence or chaining fetchlands trips the discount without noticing, and the punishment lands on two axes at once: a double Stone Rain to set the manabase back plus a sweep that clears anything short of a real body. At full price it is unplayable, a dead card you would never cast; the spell only exists at the reduced cost, and the distance between the printed number and the punished one is precisely the lever the design pulls. What separates this from cards that punish only mana or only the board is that it taxes both, so a player who overextends development and creatures in the same indulgent turn pays twice for the greed. The cost is read-the-table interactive rather than proactive: you hold up mana and wait for the opponent to stretch too far instead of dictating tempo yourself, which makes it less a removal spell than a wager on an opponent's discipline failing at the wrong moment.