Clockwork Beast

A wind-up toy with a finite spring: the seven +1/+0 counters are a battery the card spends every time it swings or blocks, and the upkeep-restricted rewind is the meter that cranks it back to full only by paying mana and committing the turn's earliest window to maintenance rather than attacking. The beast swings for full the first time, less the next, and eventually winds down to a 0/4 wall unless its pilot keeps feeding the bill. This is balance built through bookkeeping rather than rate: a six-mana creature attacking for seven was understood as too much, so the card was given an obsolescence clock and an activation window narrow enough (only your own upkeep, before you ever reach a main phase) to keep the rewinding from being free or automatic. The choice of +1/+0 counters rather than the more familiar +1/+1 is part of the same discipline: the toughness never grows, so the beast is always trading into the same removal and chump-blocking the same threats no matter how wound-up it is. A historical artifact in both senses, and a useful reference point for how early Magic priced large creatures: not by what the body cost to cast, but by what it cost to keep the body running.