A-Ochre Jelly

The gelatinous cube that splits when you cut it, rendered as a scaling threat that literally halves on death. The X in the cost buys the counters, and the counters are what the whole card is about: kill it while it carries two or more, and the Split trigger spawns a single copy holding half that many at the next end step, so a clean answer converts one large body into a smaller replacement instead of clearing the board. That structure inverts the usual math on a big creature. Ordinarily the defender wants to trade down: block, remove, absorb. Here removing the Jelly while it is fat hands back a fresh problem, and trample means the shrunken heir still bleeds damage through chump blocks. The dungeon-crawl flavor does real mechanical work; anyone who has watched a party hack a slime and watch it divide recognizes the geometry. Ward is the tax that keeps the split from being a bargain: it makes the opponent pay to trigger the very effect that punishes them, forcing a choice between spending extra to shrink it and simply letting a growing trampler connect. The rounding-down clause is the natural limiter, since each generation loses half its mass and the chain runs dry after a few divisions rather than snowballing forever. It is a body designed so that dealing with it and feeding it are the same action, and the counter arithmetic is the entire tension.