Impending Disaster

The clock is the whole design. Most Armageddon-style effects ask you to pay full retail for the symmetry-break, then accept that the symmetry favors whoever was ahead on board. This one inverts the bargain: it costs almost nothing up front and then hangs over the table as a threat, counting down toward the seventh land like a fuse you cannot easily cut. The trigger checks total lands on the battlefield, not just yours, so the timing belongs to the whole table rather than to the controller alone. That hands the deck a window: an aggressive shell wants the wipe to fire while it has bodies in play and the opponent has none, and the cheap front-end means it can drop the enchantment early and race to set up that asymmetry. What keeps the bargain honest is that you do not get to choose when it goes off. Once the seventh land hits, it sacrifices and detonates on your upkeep whether or not the board state has resolved in your favor, and a flooding mirror can blow up both players who would rather have kept their mana. It is land destruction reframed as a commitment device: you announce the doomsday count for two mana and then have to build a game plan that profits from the explosion you scheduled. The cleverness is in making the destruction inevitable and the timing rigid, then daring you to bend the rest of your deck around it.