Relic of Legends

Most fixing rocks give you one tap and stop. This one keeps its own tap intact, then bolts on a second faucet: any untapped legendary creature you control can be tapped for colored mana, so bodies already sitting on the battlefield double as fixing. Two colored sources can come online in a single turn when a deck is starved for them, which separates this from a plainer rock. The cost hides in the verb. Tapping a legend for mana spends a would-be attacker or blocker, so the ability points naturally at commanders too fragile to swing into open mana and at utility legends whose tap had nothing better to do. The oracle text also draws a firm line: only legendary creatures feed the second ability, so ordinary mana dorks contribute nothing, and legendary artifacts or enchantments do not count either. That restriction quietly favors decks stacked with legends, where each additional one is another source waiting to be tapped. The first activation reads like any color-smoothing artifact; the second outlet is what turns a static ramp piece into an engine whose ceiling rises with every legend you can keep upright.