Mono-Blue Terror has no artifacts and no graveyard-dependent cards beyond self-mill fueling Tolarian Terror and Cryptic Serpent's cost reduction, so Nihil Spellbomb's exile-a-graveyard mode doesn't meaningfully disrupt their plan since they only need the cards in the graveyard, not protect them from removal. Duress strips Counterspell or Dispel before you deploy your threats, letting your removal and creatures resolve cleanly against their permission suite. We avoid bringing in Faerie Macabre since exiling a couple of instants/sorceries from their graveyard doesn't meaningfully slow Tolarian Terror or Cryptic Serpent's cost reduction long-term, and keeping mainboard removal intact matters more against their efficient threats.