Mono-Green Eldrazi wants to ramp into giant threats like Emrakul or Ulamog, so racing before they hit critical mass is essential, but Consign to Memory can counter their colorless spells and triggered abilities — such as Sowing Mycospawn or Eldrazi cast triggers — to keep their ramp and board presence in check. Surgical Extraction is much better, stripping their top-end threats (Emrakul, Ulamog, Ugin) from the graveyard after a Malevolent Rumble mills them, eliminating all remaining copies from their hand and library. Mutagenic Growth and Violent Urge are cut in favor of proactive disruption, since this matchup is about denying their ramp payoffs while racing on the ground. Mulligan aggressively for fast, low-curve hands.

Boros Energy is full of small creatures like Ragavan, Ocelot Pride, and Guide of Souls, all of which die cleanly to Unholy Heat for one mana, with the delirium-fueled 6 damage mode covering bigger threats like Boromir or Voice of Victory. Surgical Extraction can strip a copy of Ragavan or Ajani, Nacatl Pariah before it snowballs, denying them a second copy later in the game. Mutagenic Growth and Violent Urge are cut since this is a battle of who removes the opponent's key creatures first, not a combat-trick war, and Boros has efficient removal of its own (Galvanic Discharge) that punishes overcommitting to combat math. Keep the low curve for a fast, disruptive draw.

Affinity is an almost entirely colorless/artifact deck, making Consign to Memory extremely effective at countering their colorless spells like Mox Opal, Mishra's Bauble, or Engineered Explosives, plus stripping Urza's Saga's chapter triggers and Mox Opal-enabled plays. Meltdown can wipe their board of cheap artifacts (Mox Opal, Welding Jar, tokens, even Kappa Cannoneer at higher X) in one sweep, which is devastating against their artifact-synergy shell. Mutagenic Growth and Violent Urge are cut since they do nothing to stop their artifact engine and this matchup is decided by disrupting their critical mass of cheap permanents. Prioritize Meltdown timing to catch multiple artifacts at once rather than casting it reactively to a single threat.