Huatli's Raptor

Proliferate spent its early life bolted to artifact and infect shells, a compounding mechanic that only paid off where counters had already accumulated: charge counters, poison counters, loyalty. Grafting it onto a two-mana Selesnya body relocates it to the two colors most likely to be flooding the board with +1/+1 counters and planeswalkers, exactly the permanents it wants to feed. That relationship makes this a payoff rather than a curve-filler: its ceiling is set by what has already hit the table, since proliferate grows only what is already there. Loyalty on a planeswalker climbs a notch, every creature carrying a +1/+1 counter swells, any charge counter ticks up, all off one enters-the-battlefield trigger. Even a board with nothing on it can still find work, because proliferate can name players as well as permanents; a poison or energy count on someone will oblige. The vigilance does more than the rate suggests: a body that attacks without leaving you undefended keeps the counters-matter engine parked on the battlefield, where a flicker or reanimation effect can wring the trigger out of it a second and third time. The whole design intent is to plant proliferate somewhere its owner is naturally minting the counters, rather than leaving the mechanic siloed in the poison-and-artifact corner where it started.