Winter, Cursed Rider

The tell is what the exhaust ability eats: artifact cards exiled from your own graveyard, converted one-for-one into a board-wide shrink on every other nonartifact creature. That fuel line reveals the whole build. This is a two-mana Dimir shell that wants artifacts flowing through the yard, because the payoff scales with X, and X is capped only by how much scrap you have accumulated. The -X/-X hits nonartifact creatures only, so an artifact-creature deck walks out of its own contraction almost untouched while opposing bodies evaporate; that asymmetry is the point, and it means you build the board that survives its own answer. The Ward it hands to your artifacts does not make them untouchable: two life is a tax, not a wall, and a determined opponent will pay it to kill something that matters. What the tax buys is friction and value, a two-life toll on every removal spell aimed at your artifacts that slows the disruption feeding the sweeper rather than stopping it. Exhaust is the ceiling here: the mass shrink fires once, ever, so even after you pay the and tap, you get a single detonation, not a repeatable control loop. This is a design built toward one big turn, not a grind, where the graveyard is a resource pool and the artifacts are both engine and armor, and the sweeper's size is pre-paid in discarded scrap.