Domain Zoo swings with a horde of small aggressive creatures like Wild Nacatl and Territorial Kavu; Pyroclasm's 2 damage wipes most of their one-toughness threats before they can attack. Mystical Dispute is cast cheaply against their blue spells like Stubborn Denial and their own sideboard Consign to Memory/Mystical Dispute. Thought Scour and Persist are too slow against this fast-clock matchup, so they're cut for more immediate interaction. Keep Fatal Push and Thoughtseize for their early threats and hand disruption, since racing is risky against Ragavan and Scion of Draco backed by burn.