Eldrazi wants to ramp into Urza's Saga constructs and Emrakul, the Promised End, so Force of Vigor is excellent against Saga and their artifact mana (Talisman, Springleaf Drum). Faerie Macabre can discard to exile two graveyard cards, disrupting the cards Malevolent Rumble puts into their graveyard, Emrakul's cost reduction, and their other graveyard synergies cheaply. Dismember's -5/-5 cleanly answers Basking Broodscale or Sowing Mycospawn, but it won't kill the 6/6 Devourer of Destiny. Trim the slow top-end Skyturtle/Riverwinder/Waker since the matchup rewards proactive disruption over big blockers.
Rakdos Delirium leans heavily on cheap blue-adjacent interaction is minimal, but Mystical Dispute still snipes their occasional blue-side sideboard cards and is a flexible catch-all counter they must pay around; Faerie Macabre lets you proactively exile Stitcher's Supplier, Street Wraith, or escaping Nethergoyf triggers before delirium turns on. Colossal Skyturtle and Curator of Mysteries are your most passive, high-cost cascade hits against this fast graveyard aggro deck, so trimming them keeps the curve lean without touching your core cascade payoffs like Shardless Agent, Violent Outburst, or Living End. Living End is still strong here since their graveyard fills itself but their creatures are mostly small and die easily to the reset. Keep Endurance and Subtlety in to fight Nethergoyf/Moonshadow escape and their Orcish Bowmasters.
Esper Control is full of blue spells, so Mystical Dispute for {U} is excellent against Teferi, Time Raveler, Narset, Day's Undoing, Jace, and their counterspells like Spell Snare and Consign to Memory. Their Narset caps us at one card drawn per turn, and their Teferi forces us to cast spells only at sorcery speed, which cuts off our flash and instant-speed plays. Trimming some of the slower, less impactful creatures that don't advance the game plan under those restrictions is worthwhile. Keep the core Living End and Force of Negation plan intact: Living End is our best way to rebuild after their sweepers, and Force of Negation answers their noncreature spells like Teferi and Narset.
Suggested new sideboard cards to pick up for the current metagame.
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