Phyrexian Snowcrusher

Take the Juggernaut chassis (a beater that must attack each combat, the trade-off that has priced this kind of body since the earliest artifact creatures) and graft the snow supertype onto its growth ability. The result is a 6/5 that lands a turn or two later than the classic version but climbs under its own power, spending for each point of +1/+0 you want. That two-mana-per-pump cost is the whole point: in a deck flush with snow mana, a creature that already cannot be talked out of attacking turns surplus mana into incremental damage, scaling the threat without drawing a second card. The forced-attack clause reads as a downside and mostly is, but it cooperates with the activation: you were swinging anyway, so the mana you sink in is never wasted hedging on whether to commit. The snow tax does the balancing work. Each point of growth wants a manabase paying snow into the curve, and at two mana a pop the ceiling is steep enough that only a deck built around the supertype gets there. Splash snow as a partial commitment and this is a slow, near-vanilla body walking into combat on a leash. It is a clean piece of mechanical synthesis: the unstoppable artifact engine of war rebuilt so its payoff scales with an entire deckbuilding theme rather than sitting inert in a single slot.