Ozolith, the Shattered Spire

The replacement effect is the whole architecture here: every +1/+1 counter placement on your artifacts and creatures gets one extra passenger, so a single +1/+1 counter becomes two, a proliferate lands wider, an adapt or a modular trigger scales one step past what the source printed. Crucially this works on the input side rather than adjusting a total already on the board, which means it never touches counters that are already sitting there and instead rewards a deck that keeps feeding the battlefield fresh counters. Because it is legendary, you get exactly one copy doing this work, so the payoff is concentrated in a single cheap permanent rather than diffused across redundancy. The design lineage runs back to the green counters decks that wanted one permanent to amplify the whole plan: Doubling Season did it for tokens and counters both, Hardened Scales added a plus-one on counter placement for one mana. This sits nearer the latter, an artifact rather than an enchantment (dodging the enchantment removal those decks feared) and cheap enough to be the two-drop that switches on everything after it. The activated ability gives the card a floor when the engine is not assembled, seeding its own counters at sorcery speed. Cycling is the quiet discipline the whole build-around depends on: greed this specific needs an exit, and pitching the card for a fresh draw keeps it from stranding an opener where it would otherwise sit inert with nothing to amplify.