Izzet Delver races with Dragon's Rage Channeler backed by Lightning Bolt and free countermagic in Force of Will, so Leyline of Sanctity (free from an opening hand) makes their Lightning Bolt and any other targeted spell aimed at our face irrelevant. Into the Flood Maw is efficient at bouncing a growing Dragon's Rage Channeler to reset their clock while we assemble our own kill. Unmask is weak since we're racing rather than grinding and they hold up so much free interaction that a resolved discard rarely matters, so we trim it for resilience and tempo answers. Bridge from Below is also less reliable here, so we trim it to make room for interactive cards.