The EPIC Storm wants to chain rituals and cost reducers like Lion's Eye Diamond and Mox Opal into Tendrils of Agony or an Echo of Eons loop, so Tormod's Crypt can proactively exile their graveyard to cut off Echo of Eons' flashback and any Beseech the Mirror-fetched recursion plans before they go off. Force of Negation is excellent free interaction on their turn to counter a key noncreature spell like Tendrils of Agony, Burning Wish, or Echo of Eons before they combo off. Sink into Stupor and Thundertrap Trainer are too slow and don't meaningfully interact with their combo pieces, so we trim them for proactive disruption. Note Veil of Summer can make our blue spells uncounterable-resistant since it grants hexproof from blue, so timing our Force of Negation before they have mana up for Veil matters.