WBR is an aggressive midrange deck with efficient threats like Moonshadow and Hardened Academic plus removal like Requiting Hex, so we want to strip their removal and stabilize with lifelink. Duress takes away their noncreature spells like Requiting Hex or Practiced Offense before they can use them against us. Elegy Acolyte's 4/4 lifelink body blocks their aggressive creatures well and refuels our hand as the game goes long. We cut Dissection Practice's small effects and Dark Knight's Greatsword's painful equip cost since we need to prioritize card advantage and stabilizing life total in this race.