Lava Tubes

The depletion-counter cycle that Ice Age built its dual lands around, and the design idea is honest about its cost in a way later duals stopped being. Each tap stores a depletion counter, and a land carrying one stays tapped through your next untap step; you get mana now and skip the land the following turn. The math is plain: it produces one of two colors every other turn, which over a long game averages out to roughly half a real dual. That rhythm was the entire point. This was an era when Wizards balanced fixing with friction rather than life payment or tapped-on-entry clauses, and the depletion mechanic is the most literal expression of that philosophy: the land taxes its own availability instead of taxing you. The timing is the cruel part, and it runs the opposite of what intuition suggests. The untap step comes before upkeep, so the land first fails to untap, then sheds its counter during upkeep; it sits tapped and useless for that whole turn, and only comes back online the turn after. It reads as a fair compromise on paper and plays as a frustrating one in practice, which is exactly why the depletion duals never became a template Wizards returned to. They are a fossil of a balancing instinct the game outgrew: the fixing-as-tempo-cost school, preserved cleanly in five color pairs that asked you to pay in time.