Spike Feeder

The Spike cycle gave Tempest block a creature whose body is also its ammunition: a fixed stockpile of +1/+1 counters that can be spent in two directions and never refilled. This one is the cleanest version of the idea. Each counter is a binary choice between two life and growing another creature, and once the counters are gone the 0/0 frame falls off the table. That self-consuming structure is what lets a flexible three-mana value engine stay honest: every point you extract shrinks the source until nothing remains. The life-gain mode reads as throwaway until you notice it has no mana cost, no timing restriction, and no rate limit beyond the counter supply, which is precisely what turns the card into a combo piece rather than a midrange afterthought. Pair it with anything that replaces a removed counter whenever you gain life (the classic loop runs through Heliod, Sun-Crowned, where Spike Feeder's own ability gains the two life that prompts Heliod to put the counter back), and the slow trickle the design intended becomes infinite life. The counter-moving ability ages well in a counters-matters world: with no timing clause, it can shuttle growth onto a proliferate target or a death-trigger payoff at instant speed, mid-combat or in response to removal. Built as Limited filler, it turned out to hold a combo key two decades later, because the designers handed it a free, repeatable life-gain valve and trusted the counter count to do the balancing.