Infernal Darkness

A mana-denial lock in the family of Blood Moon and Contamination, and one that has aged into a curiosity precisely because of how its two halves fight each other. The static effect is a global manabase rewrite: every land in play produces black when tapped for mana, regardless of color or type, which turns an opponent's carefully built five-color manabase into a swamp and leaves their nonblack spells stranded. The escalating tax holding it in check is what makes the card self-defeating: each turn the upkeep climbs, and because it is paid in life as well as black mana, the controller is racing a clock that punishes the very thing the enchantment is supposed to guarantee. Weaponizing it means stealing a small window: a few turns where your opponent cannot cast and you can, before the upkeep cost (and the life loss compounding alongside it) buries you instead. That self-limiting structure is the mark of early cumulative-upkeep design, where the mechanic was meant to make symmetrical or near-symmetrical lock effects available without making them permanent. It sits in that family alongside the other Ice Age upkeep enchantments, a generation of cards built around the idea that a powerful effect could be safely printed if the player had to keep buying it back at escalating cost. The lock is real; the question the card poses is whether you can win before you stop being able to afford it.