Granulate

Mass artifact removal with a deliberate ceiling: it sweeps the cheap nonland stuff and leaves the expensive payoffs standing. That cutoff (mana value four or less) is the whole design conversation, because it carves red's answer to artifacts into a precise shape. Where a colorless catch-all like Shatterstorm punishes every artifact equally, this trades comprehensiveness for color-pie identity. Red has always been the color that smashes Mishra's contraptions and mana rocks, and the cap aims the sweeper at exactly the layer of the board where artifacts do the most cumulative work: the dorks, the small equipment, the cost-reducers, the early-curve engine pieces that a deck stacks to snowball. The big bombs, the things actually worth eight mana, sail through untouched, which is the friction that keeps a four-mana board wipe from being unconditional. It is a sorcery, so it cannot ambush an artifact attacker mid-combat; you commit to the sweep on your own turn, after surveying what the cap can and cannot reach. In an era when artifact aggression and mana acceleration leaned heavily on the bottom of the curve, that targeting was a sharper tool than a blunt "destroy all artifacts" would have been: you keep your own expensive pieces while erasing an opponent's cheap engine, asymmetry that a true sweeper never offers.