Wurmwall Sweeper

Station is a slow-cook mechanic: a permanent that lands inert and grows as you feed it, and this one turns that ramp into a payoff schedule. It arrives as a 2/2 that isn't a creature at all, filters your next draw with surveil on entry, and then sits waiting for charge counters. The wrinkle is that stationing happens at sorcery speed and scales with the power of whatever you tap, so a single big attacker in the second main phase can vault it past the flying threshold in one activation rather than incrementally. That creates a genuine tension in how you build toward the 4+ line: nickel-and-dime it with small bodies across turns, or withhold one heavy hitter to hurdle the gap in a single motion, trading tempo now for evasion later. Because the counters persist, progress toward the threshold is permanent even if the assembly stalls; you never lose ground already gained. But the transformation cuts both ways. Once it crosses 4+ it becomes an artifact creature and stays one (there is no end-of-turn revert the way a Vehicle crews and un-crews), which means the very thing that makes it a threat also makes it vulnerable: a sweeper that hits creatures now hits this too. The payoff at 4+ is only Flying, so this was never a card that wins by itself; it's a utility artifact that quietly upgrades into an evasive attacker as a game grinds long, with the surveil giving it something honest to do the turn it comes down.