Mono-Green Eldrazi wants to ramp into Emrakul, the Promised End and grind with Kozilek's Command and Devourer of Destiny, so Galvanic Blast comes in to pick off Basking Broodscale and early Eldrazi Spawn tokens, hitting for 4 off metalcraft against this slower deck. Vexing Bauble stays in the sideboard: it only counters spells cast with no mana spent, and it would hit our own zero-cost artifacts like Mox Opal and Mishra's Bauble far more than anything they play. Claws of Gix and a Welding Jar are too passive against a deck that isn't racing you on board, so they come out. Keep the full Tormod's Crypt and Engineered Explosives package, since graveyard disruption matters against Emrakul's cost reduction and Explosives can sweep their cheap permanents like Spawn tokens and Basking Broodscale. Explosives can't reach Devourer of Destiny, which has mana value 7.

This Gruul Broodscale combo deck wins by looping Blade of the Bloodchief with Basking Broodscale and Eldrazi Spawn tokens, so Galvanic Blast is premium removal that kills Basking Broodscale (a 2/2 until it adapts) before they can go off. With metalcraft, its 4 damage still kills a Broodscale that has already grown, and it also handles Glaring Fleshraker. Claws of Gix and a Welding Jar don't interact with the combo or pressure the board fast enough, so they're cut. Keep Tormod's Crypt and Engineered Explosives in. Crypt can strip graveyard-reliant plans like Emrakul's cost reduction, and Explosives can be set to sweep either their Spawn tokens or Basking Broodscale, depending on how many charge counters it has, though it will also hit our own permanents with that mana value.

Izzet Prowess is a fast creature-based tempo deck full of cheap noncreature spells that trigger prowess and surveil. Consign to Memory is narrower than it looks: it can only counter a colorless spell or a triggered ability. Their Mishra's Bauble is the main colorless spell it hits, since Lava Dart, Lightning Bolt and their other spells are colored. It can also stop triggered abilities like Dragon's Rage Channeler's surveil, Monastery Swiftspear's prowess, and Slickshot Show-Off's pump. Whipflare sweeps their Dragon's Rage Channeler, Monastery Swiftspear, and Slickshot Show-Off (all 1-2 toughness before pump) without touching our own artifact creatures. Preordain and Metallic Rebuke are too slow and reactive against their low curve, so they make room. Keep Mishra's Bauble, Mox Opal, and the full artifact synergy package since this is a race we can win on our proactive plan.