Izzet Spellementals wants to chain cheap cantrips and land Hearth Elemental or Eddymurk Crab at a discount, so Duress proactively strips a key piece like Prismari Charm or Traumatic Critique before it can disrupt your board. Ghost Vacuum exiles cards from their graveyard, slowing the cost reduction on Hearth Elemental and Eddymurk Crab while also denying value from their own Ghost Vacuum. Dark Knight's Greatsword is too slow and clunky when the opponent has cheap bounce and removal like Prismari Charm and Burst Lightning to blow you out on the equip. Desolation Prowler's life-payment pump is risky against a deck that can flip Traumatic Critique or Burst Lightning at your face, so it comes out for the more proactive disruption.

UR Aggro leans on cheap cantrips and growing threats, so Duress gets ahead of the game by taking a key spell before it can enable their velocity plan. Ghost Vacuum exiles graveyard cards to blunt Hearth Elemental's cost discount and denies any incidental graveyard value, while also being a cheap early play that doesn't ask much of your mana. Dark Knight's Greatsword is too slow against a deck full of cheap interaction and removal like Burst Lightning that can pick off the equipped creature. Desolation Prowler's repeated life payments are dangerous racing a deck with direct damage like Burst Lightning, so it steps aside for more resilient disruption.

Dimir Midrange is loaded with countermagic (Spell Pierce, Spell Snare, We Say Thee Nay!) and reactive removal (Bitter Triumph, Requiting Hex), so Duress proactively strips those answers before we commit our threats. Gollum the Abandoned provides a recursive threat that punishes their removal-heavy plan. Dissection Practice is too marginal against a deck full of efficient removal and card advantage engines like Enduring Curiosity, and Dark Knight's Greatsword is clunky against a deck that can just Bitter Triumph the equipped creature.