Amulet Titan wants to cheat out Primeval Titan or ramp into Scapeshift with free cost reductions from Amulet of Vigor and Summoner's Pact; Abrupt Decay can destroy Amulet of Vigor or an early Arboreal Grazer (both mana value 3 or less) without fear of a counter, and it also answers Primeval Titan outright. Vexing Bauble counters their Summoner's Pact, which is cast for {0}, cutting off a key piece of their ramp engine for free. We trim some of our slower value creatures since the matchup is about disrupting their engine before they assemble enough mana to go off, not grinding card advantage.