The Mana Rig

Multicolored-matters payoffs usually live in the command zone or on a creature that wants to attack; putting one on a colorless three-mana artifact is the quiet trick here, because any deck can run it regardless of what colors it plays, and the trigger only cares that the spells you cast are multicolored. What it rewards is a manabase built to cast gold spells, and what it hands back is Powerstones: mana locked to artifact spells and activated abilities, which points the whole engine toward big colorless payoffs rather than just accelerating the deck it sits in. That restriction on the tokens is what keeps the ramp from spinning free; you cannot dump the extra mana back into more gold spells, so the payoff has to loop through artifacts instead. The activated ability closes the circuit by turning that stockpile into cards: an dig that scales with how much mana (Powerstone or otherwise) you have banked, letting you look deep into your own library and keep the best two while burying the rest. It is a self-contained value structure. Casting gold spells feeds the rock, the rock feeds artifact costs and its own draw, and the draw refills the gas, all bolted onto a mana value cheap enough to land early and start compounding.