Prismatic Ending answers Tamiyo, Inquisitive Student and Teferi, Time Raveler, two problematic nonland permanents that dodge Swords to Plowshares' creature-only restriction or otherwise generate ongoing card advantage. Clarion Conqueror is a resilient flying beater that also shuts off Tamiyo's planeswalker loyalty abilities and Teferi's activated abilities, making it hard for WU to profitably interact with on the ground. Cabal Therapy is weak against a deck full of cheap cantrips and countermagic rather than a tight hand of key spells to strip, so it comes out. Goblin Bombardment's sacrifice outlet is low-value here since this matchup is about resolving and protecting threats rather than grinding small trades.