Powerful Broker

Most proliferate effects trade breadth for depth: they touch every counter across the board but add only one to each. This narrows the target to a single permanent or player, then pays that narrowness back by scaling with variety rather than quantity. For each distinct kind of counter sitting on the target, it adds one more of that kind. On a planeswalker carrying only loyalty, that is a single tick, no better than a lone proliferate. On a creature stacked with a +1/+1 counter, a keyword counter, and an oil counter, one tap lands three at once, all concentrated where you have already invested. The payoff is not the total counters present but how many types you have assembled, which turns deckbuilding toward a diversified stack of counter kinds instead of one tall column. The sorcery-speed clause is the pressure valve on what would otherwise be a repeatable escalator: no end-of-turn ambush growth, no instant-speed loyalty spike the turn before an ultimate, no combat-trick blowout. Each activation is a windup the opponent watches coming and gets a full turn to answer. And because the ability lives on a tap rather than a one-shot spell, it is an engine, not a moment: it rewards a board built to keep feeding varied counters onto a single anchor, then compounds them one kind at a time, turn after telegraphed turn.