Abrupt Decay can't be countered, so it dodges Daze and Force of Will while answering Tamiyo, Inquisitive Student (mana value 1), Phelia, Exuberant Shepherd (mana value 2), or an early Teferi, Time Raveler (mana value 3). Teferi restricts us to sorcery timing, so we want to remove it on our own turn before it gets going. We trim Boseiju since we want proactive, uncounterable answers instead. Gaddock Teeg is not part of the plan. It would stop Force of Will (mana value 5), but it does not stop Teferi (mana value 3). It would also lock our own Natural Order and Green Sun's Zenith, it needs white mana that only Birds of Paradise and Talon Gates of Madara can make, and Karakas can bounce it. Sylvan Safekeeper stays in, since it can protect our key creature from Swords to Plowshares.