Mono-Green Eldrazi ramps with Eldrazi Temple and Ugin's Labyrinth into Ulamog, Ugin, and Emrakul, the Promised End, with Fight Rigging sneaking threats in early. Consign to Memory is tailor-made for this: for one mana it counters their colorless spells outright, and critically it counters Emrakul's cast trigger so they never take your turn even if the 13/13 resolves. Erode handles the early Slumbering Trudge and Fanatic of Rhonas beats and removes Sowing Mycospawn (though its land search triggers on cast, so Erode won't prevent the search). Pithing Needle names Ugin, Eye of the Storms — loyalty abilities are activated, so Needle shuts down its loyalty abilities (though its triggered ability on casting colorless spells still functions). Keep Shadowspear in and remember its second mode: one mana strips indestructible from Ulamog, the Ceaseless Hunger so Erode or lethal combat damage actually destroys it. They are slower than the combo decks but inevitable, so take the aggressive role immediately; an early Inkmoth with Hammer ends it before Ugin mops up your colored creatures. Metallic Rebuke rots in the mid-game once their lands make five-plus mana, so it comes out along with the slow trinkets.
Boros Energy floods the board with Guide of Souls, Ocelot Pride, and Ajani tokens, then converts energy into removal with Galvanic Discharge and burns through blockers with Goblin Bombardment. Erode is efficient removal for Guide of Souls (their best card against you), Seasoned Pyromancer, or a flipped Ajani. Surge of Salvation is quietly excellent: both Galvanic Discharge and Goblin Bombardment are red sources, so one mana can protect your equipped creature through their entire removal turn while also giving hexproof against Static Prison. Pithing Needle names Goblin Bombardment — without it their board can't interact with an equipped Ornithopter in combat at all. All four Metallic Rebuke come out; their curve of one-drops makes it embarrassing, and this becomes a pure board matchup where you'd rather have another body or piece of interaction. Post-board expect Wear // Tear on your Hammer or Saga and Obsidian Charmaw on your lands — spreading equipment across two carriers with Kíli's free equips beats holding everything on one creature. Your Inkmoth Nexus is the cleanest wincon since their gained life from Guide of Souls doesn't matter against poison.
Affinity is the pseudo-mirror: their Urza's Sagas, Mox Opals, and cheap artifacts race yours, but Kappa Cannoneer and Pinnacle Emissary go bigger while Engineered Explosives can wipe your whole one-drop board on one. Erode answers Emry and Pinnacle Emissary efficiently — but check ward before pointing it at Kappa Cannoneer, since the ward tax of four makes that a terrible trade; race the Kappa with a Hammer-equipped threat instead. Pithing Needle is flexible: their Urza's Saga on the play, Engineered Explosives if you've seen it, or Emry against the grind. Consign to Memory counters Engineered Explosives (colorless) and can even counter a Saga chapter trigger in a pinch. Vexing Bauble stops their Mox Opal and Mishra's Bauble — deploy your own zero-cost artifacts first, because it counters yours too. Watch for Whipflare post-board: it kills Stoneforge, Kíli, and Puresteel while sparing their key artifact creatures (and your Memnites). Two Memnite and the fragile trinkets come out to make room — keep your board tight and your threats equipped.
Suggested new sideboard cards to pick up for the current metagame.
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