This matchup is a race against a colorless-heavy artifact/land ramp shell; Meltdown blanks Urza's Saga constructs and Vexing Bauble. Spell Snare has few good targets since most of their key spells (Devourer of Destiny, Kozilek's Command, Emrakul) cost more than 2, so it comes out. Surgical Extraction can strip a second Basking Broodscale or Devourer of Destiny after Unholy Heat/graveyard interaction, and Hurkyl's Recall resets their Urza's Saga tokens and equipment. Keep Counterspell up to stop Emrakul, the Promised End, and Force of Negation to stop Kozilek's Command.

Mirror-ish matchup where being proactive and having cheap, efficient answers matters most; Mystical Dispute costs just {U} against their blue spells (Expressive Iteration, Preordain, their own Consign to Memory) and is excellent value. Stern Scolding cleanly answers Monastery Swiftspear and Slickshot Show-Off, both power/toughness 2 or less. Spell Snare still has fine targets (Expressive Iteration, Cori-Steel Cutter) but the extra copies are worse than upgrading to Mystical Dispute; trim one Consign to Memory since they don't rely heavily on colorless spells. Play a low curve and race with Ragavan and Murktide Regent.

Esper GenericBlink is full of small, resilient creatures (Phelia, Orcish Bowmasters, Flickerwisp) so Fire Magic's Fira mode for {2} sweeps most of their 1-2 toughness threats cheaply. Blood Moon is strong here since their manabase leans on many tapped dual/surveil lands and Flooded Strand/Marsh Flats fetches, disrupting their colors while your own basics are largely unaffected. Spell Pierce loses value against a deck that can play around 2 extra mana easily with Thoughtseize-fueled information; Spell Snare still hits Orcish Bowmasters, but Teferi is 3 mana so it's safe to trim one for the sweeper plan. Keep Counterspell for Solitude and Overlord of the Balemurk, and Force of Negation for noncreature spells like Teferi.