Simic Manipulator

Threaten effects normally rent a creature for a turn; this one buys it outright, and the price is counters you spent the whole game stacking. The two abilities feed each other in a way that reads cleanly only once you watch them work together: evolve grows the body whenever a creature with greater power or toughness enters under your control, and the steal ability spends those same counters to take any creature whose power is at or below the number you remove. Theft is a withdrawal from an account you have to keep refilling, but the refill is half-built into the design: shrinking back toward the 0/1 base makes the next creature you play more likely to clear the evolve threshold, so each steal lowers the bar for the next counter. The gate is power, not toughness, which means undersized boards are exactly what this preys on: a 0/1 that has stacked a few counters can reach across and peel small utility creatures, mana dorks, and chump blockers off an opponent before it ever threatens the genuine beaters. And because the activated ability carries no sorcery-speed clause, the steal fires at instant speed: at the end of an opponent's turn, mid-combat to swing a block, whenever the counters are there. It sits where the blue-green ramp-and-grow identity meets the older mind-control lineage, asking you to keep landing bigger creatures so a 0/1 can grow tall enough to commandeer the opponent's.