Izzet Prowess is extremely low to the ground with Monastery Swiftspear, Dragon's Rage Channeler, and burn spells, so Solitude is premium free removal to answer their best early threat before it gets delirium bonuses. Pithing Needle can name Cori-Steel Cutter, since its equip ability is an activated ability and Needle stops it from being activated. The Cutter's flurry trigger still makes Monk tokens, but they can't be equipped by hand. Needle can also name another activated ability they bring in, like Mishra's Bauble, so hold it flexibly as a value slot. This matchup is a damage race, so prioritize efficient blockers and removal over slower artifacts. Watch for their Consign to Memory countering our colorless spells like equipment and artifact creatures post-board.