Thoughtseize is critical to proactively strip Show and Tell or Omniscience before they can assemble their combo, since answering those pieces after they resolve is far more difficult. Choke is devastating against their heavily blue, Island-dependent manabase, shutting off Force of Will, Ponder, and Brainstorm mana by keeping their Islands tapped down. Damping Sphere taxes their Ancient Tomb and City of Traitors mana while increasing the cost of multiple spells cast in a single turn. We overload on proactive discard and mana disruption since reactive plans are weak against a deck that only needs to resolve one enchantment to win; since trimming a second copy of Icetill Explorer beyond the single copy in our maindeck is not possible, we adjust the cut to Once Upon a Time instead.