Izzet Delver is a fast tempo-aggro deck built around Dragon's Rage Channeler, Murktide Regent, and Cori-Steel Cutter, backed by Force of Will, Daze, and Lightning Bolt, so we want resilient bodies that survive Lightning Bolt and pressure them back quickly. Trumpeting Carnosaur's 7/6 trample body is too big for Lightning Bolt to profitably answer, and its discover 5 refills our hand after their disruption; its activated mode can also kill a Dragon's Rage Channeler or Cori-Steel Cutter token. Ingot Chewer's evoke mode cheaply answers Cori-Steel Cutter, denying them the equipment's trample/haste buff. We cut Maelstrom Wanderer for being too slow and Tibalt's Trickery since it's a risky gamble when we'd rather deploy proactive threats to race their aggressive clock.