Gauntlet of Power

The doubling effect here is the half that gets remembered, and it descends directly from Gauntlet of Might, the old red-only artifact that pumped your team and doubled Mountain output. This is the five-color generalization: pick your color when it enters, and every basic of that color now taps for two. That single design move turns the card into a mono-color ramp engine, the kind of accelerant that doubles your most plentiful resource on every tap. The +1/+1 anthem is the tax that pays for it, and the reason this is symmetric where its ancestor was not: it does not name a controller. Choose green, and every green creature on the board grows, opponents' included, while every Forest in play (yours and theirs) doubles. That symmetry is the design tension the card refuses to resolve in your favor, which is why it belongs to mono-colored decks whose opponents are not also drawing on the chosen color: the basic-land clause and the anthem are gifts to anyone sharing your color, so the card wants you committed to a single color while your opponents are committed to others. It rewards going all-in on one hue, then hands the whole package to anyone foolish enough to mirror you. As ramp it is slow at five mana and color-locked at the choice, but the payoff (doubled mana from a deck of one basic type) is the kind of compounding that one-color ritual-style strategies have always been built to abuse.