Izzet Delver is another Force of Will/Daze deck backed by Wasteland, so Boseiju, Who Endures again gives us a proactive land that can destroy their Wasteland or a nonbasic before it strands us, while dodging countermagic via Channel. Thoughtseize lets us proactively strip a protective counterspell ahead of our combo turn. We are not bringing in Pulverize since they run no artifacts worth blowing up. We trim one land and Song of Creation, which is too slow against a deck that can race us with Murktide Regent and burn.