Dream Halls
A cost-replacement engine that swaps the entire mana economy for the card economy, and the symmetry is the only brake the design left on. The replacement applies to every player's spells, not just yours, but the practical asymmetry is enormous: a deck built to abuse it stocks expensive, color-matched bombs and treats its own hand as fuel, while an unprepared opponent gets a clause they cannot meaningfully use. What makes the rate so dangerous is that the discount scales with the cost of the spell. Discarding a one-mana cantrip to cast a six-mana payoff is the same transaction as discarding it to cast a two-drop, so the cards that break it hardest are the most expensive things you can fit. The discard is paid as an alternative cost while casting, so the spell is already on the stack before you tip the card into the graveyard; you commit the fuel, then the payoff resolves. That puts it firmly in the lineage of fixed-cost cheaters like Show and Tell, except this one keeps working turn after turn rather than firing once. The single-color-match restriction is the real design discipline: it pushes builds toward mono-color or tightly-themed shells where every spell can pay for every other card, which is why the enchantment has always lived in dedicated combo decks rather than general goodstuff piles. Power that cares nothing for what a spell normally costs tends to find the ceiling, and this one found it quickly.
