Dimir Tempo leans on free countermagic (Force of Will, Daze) and colorless/noncreature triggers like Tamiyo's Clue and Orcish Bowmasters amass, making Consign to Memory excellent at stopping their triggered abilities and colorless spells cheaply. The extra Force of Negation lets you fight through their Force of Will/Daze for your own Chalice of the Void and Urza's Saga, which are backbreaking against their small, fragile curve. Trim the cantrip-y Urza's Bauble copies since card selection matters less when you want proactive disruption, and Kappa Cannoneer is a slower plan against a deck that wants to Wasteland you down and grind with Murktide - prioritize Chalice and countermagic instead.