Aether Hub

The trick that pays for a five-color manabase is the energy economy hiding inside it. Drop it untapped on turn one for colorless, or spend the single energy counter it brings along to fix any color exactly once, and you have a land that enters without the lifeloss, the tapped clause, or the basic-type requirement that usually polices perfect fixing. The catch is the counter is finite: that any-color tap is a one-shot unless the deck generates more energy to feed it, which is what keeps a land this clean off the format-warping list. Most decks that ran it never cared about the energy subtheme at all and simply treated it as a one-time rainbow land that taps for colorless thereafter, the rare case where the cleanest read of a card and its designed-around read point in opposite directions. It belongs to a long line of fixing lands trying to thread the same needle (City of Brass and Mana Confluence pay in life, the painlands tax you when you reach for color), but this one prices its flexibility in a renewable resource rather than a recurring cost, so a deck built to refill the meter turns a single color-fix into an engine, while everyone else gets one free pull and a colorless land forever after.