Martyr for the Cause

Proliferate usually costs a card and mana to fire: it lives on an activated ability or a one-shot spell where you pay to advance every counter you control. Bolting the mechanic to a death trigger inverts that economics. The trigger is free, and it fires on the event a two-mana creature is most likely to reach on its own, so long as it lands in the graveyard: chump-blocking, trading in combat, feeding a sacrifice outlet. Bounce it or exile it and nothing happens; the payoff is specifically the trip to the graveyard, which is exactly the destination a body like this is happy to reach. So the card becomes a delivery vehicle for whatever counter matters most on a given board, whether that is loyalty on a planeswalker, +1/+1 counters spread across a team, or the poison and charge counters that reward decks built to stack them. The name does the design work: this is a body you want to spend, not protect, and its second use begins the moment it stops being a creature. That reframing separates it from the token-generator or value-creature slot it superficially occupies. The proliferate is a single event on its own, so the decks that want it most are the ones that can send it back for another lap, through recursion or a reanimation loop, converting one free proliferate into a recurring one. As counter-matters strategies have accumulated across eras, the pool of things worth proliferating has only widened.