Wintermoon Mesa

Land destruction was the design idea here, but routed through tempo rather than removal. Where Sinkhole or Stone Rain put a land in the graveyard for good, this one sacrifices itself to tap two target lands: the opponent keeps the cards but loses the mana for a turn, and you spend your own land to do it. That trade is the whole pitch. To deny the mana before an opponent can spend it, you activate during their upkeep, which makes the play a deliberate one: a soft Time Walk that costs you a permanent and most of your turn for a single turn of delay. Tapping two lands matters most when the target is sitting on one big play or trying to leave a counterspell open, but it only buys time, never ends a game, and any deck that can simply replay shrugs off the loss. The friction is severe at every step: it enters tapped, costs two mana plus the sacrifice to fire, and the effect is a one-shot. The design points at a real axis (denying untapped mana at the cost of a single permanent, rather than trading a card for a card with a removal spell), and the colorless slot was a reasonable home for an effect any deck could run. The rate just never made the math comfortable: too much setup, too little payoff, for a delay the opponent recovers from next turn.