Mono-Green Eldrazi is almost entirely reliant on nonbasic colorless lands like Eldrazi Temple, Ugin's Labyrinth, and Cavern of Souls with only 5 Forests as basics, so Blood Moon can severely cripple their manabase by turning those into Mountains. Damping Sphere further slows their ramp-heavy turns and shuts off the double mana from Eldrazi Temple. Sink into Stupor and Skateboard don't meaningfully answer their large Eldrazi threats or land-based ramp plan, so they come out. Tormod's Crypt remains valuable to strip value from cards put into the graveyard by Malevolent Rumble.

Boros Energy fields a horde of small creatures like Ocelot Pride, Guide of Souls, and Cat tokens, making Whipflare's sweep of nonartifact creatures very effective while leaving your Kappa Cannoneer and Constructs untouched. Galvanic Blast is a cheap extra removal spell that hits Ragavan or Ajani before he flips. Damping Sphere slows down their explosive turns by taxing multi-spell sequences, which matters against a deck that wants to chain multiple cheap spells in a turn. We cut the slower, more reactive Sink into Stupor and Preordain since this matchup is about surviving the early onslaught and stabilizing with sweepers.

This is the Affinity mirror, so the game is decided by who lands the better artifact threats and answers them fastest. Consign to Memory is premium here since key cantrips and artifacts in the mirror (such as Mishra's Bauble and Engineered Explosives) are colorless spells, while its replicate mode can also counter crucial triggered abilities like Urza's Saga chapters. Galvanic Blast provides cheap, efficient removal for their Pinnacle Emissary or Emry, hitting for 4 with Metalcraft active. We cut Claws of Gix since the lifegain rarely matters in a fast artifact race. Keep Tormod's Crypt in since it strips their Mishra's Bauble and Emry value from the graveyard.