Hungry Graffalon

Increment inverts the usual growth clause. Where a beefy mana sink asks you to pour mana directly into a creature to make it bigger, this one grows when you spend big mana on something else: cast a spell that costs more than its current power or toughness, and it fattens itself for free. The wrinkle is that the trigger only ever needs to clear the smaller of those two numbers, and this body always leads with its power. It enters as a 3/4, so casting anything four or more feeds it, and because power (not toughness) is the bar it must exceed, the goalpost climbs one point per counter rather than tracking the larger number. That produces a self-throttling arc anchored on the power line: it grows fastest against expensive spells early, then slows as its own power outpaces what you are willing to cast, and it never demands an activation to keep pace. Reach keeps it a useful blocker while it climbs, and the climb stalls on its own, so no separate mana sink is required. What makes it a quiet payoff rather than a build-around is that it reads your deck's top-end without asking anything extra: cast the expensive spells you were already planning to cast, and the counters accumulate on the side. The whole tension lives at the threshold. A curve stacked with four-drops and up feeds it steadily; a hand of one- and two-mana spells leaves it a 3/4 with reach and a dormant trigger.