Empowered Autogenerator

A ramp engine that pays you back on a curve instead of a line. The first tap does nothing but plant a single charge counter and add one mana; the second yields two, the third yields three, and the geometry only becomes worth the four-mana investment several turns down the road. That deferral is the whole trade: it enters tapped, and every activation both spends the turn's engine and reinvests in next turn's output, so the artifact is a bet on the game going long. What separates it from fixed-output rocks is the any-one-color clause. Once the counters stack, a single activation dumps a large monochrome pile that fills the exact role Cabal Coffers fills in mono-black, except this one is colorless to cast and color-agnostic on output, so it slots into decks that could never run those. The cost is patience and a vulnerability window: the counters live on the artifact, so removing it resets the whole investment. The accrual can be pushed faster (proliferate stacks extra counters, untap effects buy a second activation in a turn, and copying the ability adds counters twice), but every one of those is a build-around detour rather than a default. Built for the kind of deck that wants one enormous spell rather than a steady drip, it is less a mana rock than a slow-charging battery, useless the turn you need it and overwhelming the turn you finally do.