Thran Quarry

Untapped, painless, five-color fixing in a year when the alternatives were City of Brass dealing you damage every tap or duals that came into play tapped: that was the trade Urza's Saga offered, and the price was written into the end step. The land works only as long as you keep a creature on the battlefield, and the sacrifice clause is checked on every end step, yours and your opponent's alike. That timing is the whole design. A board wipe, a chump-block trade, a removal spell on your last blocker, and the quarry collapses the moment the turn winds down, often stranding you a color short on the next turn's spells. It rewards a creature-dense deck that can afford the upkeep and punishes the control shell that would most want flawless rainbow mana, which is precisely the inverse of who usually wants five-color fixing. The result is a fixing land tethered to a board state, an idea Wizards has returned to in narrower forms but rarely with this much generosity up front. The deal is real: any color, no life, no tapped-land tempo loss. The catch is that you have to keep paying rent in creatures to live in it.