River Delta

The depletion-land cycle was Ice Age's attempt to solve a problem the dual lands had created: how do you print a land that fixes two colors without simply reprinting the strictly-better originals? The answer was a tax paid in tempo rather than life or untapped status on entry. Each tap loads a depletion counter that strands the land for a turn, so the land produces colored mana on an alternating cadence: useful one turn, dead the next, until the counter clears on your upkeep. The design intent is transparent in the math, every depletion land is half a dual that you can stagger across a pair of them to approximate one reliable source. In practice the friction never justified the fixing; the format had untapped duals and painlands answering the same question with far less bookkeeping, and the depletion mechanic asks the player to track state on a permanent that does nothing for that effort. What makes the cycle worth remembering is the design lesson, not the cards: a fixing tax measured in lost untaps is invisible on the turn you tap the land and brutal on the turn you need it, which is exactly backwards from how a mana source should feel. The mechanic never returned, and the depletion lands sit as a clean example of a balancing lever that looked reasonable on paper and proved unplayable in hand.