This matchup is a grind where their colorless Eldrazi (Devourer of Destiny, Emrakul) and utility lands (Eldrazi Temple, Ugin's Labyrinth, Urza's Saga) want to go bigger than us, so Dauthi Voidwalker is excellent pressure that also exiles cards that would go to their graveyard, such as what Malevolent Rumble puts there, and keeps Emrakul from getting any cheaper. Thought Scour is weak here since we don't need the extra mill against a deck with few graveyard synergies of its own, so it is the easiest cut. Keep the reanimation plan intact since Archon and Emperor of Bones still out-race their clunkier draws.

Dauthi Voidwalker is the key bring-in here: it applies fast clock pressure with shadow, and it exiles anything that would go to their graveyard, including Kozilek's Command and the cards Malevolent Rumble puts there. That keeps their graveyard empty, which hampers Emrakul's cost reduction and Shifting Woodland's delirium. Thought Scour is a low-impact cantrip in a matchup where we need to be proactive, so two copies come out. Sink into Stupor stays in as an instant-speed way to bounce a key Basking Broodscale, Blade of the Bloodchief or a spell in response, buying a turn against the combo. Fatal Push is our main way to answer Basking Broodscale before they combo off, and it can also hit Glaring Fleshraker if revolt is on (for example after cracking a fetch land). It cannot touch Blade of the Bloodchief, which is an artifact, so we need to disrupt with Thoughtseize and pressure rather than rely on removal for that piece.

Izzet Prowess leans on colorless Mishra's Bauble and a steady stream of triggered abilities (prowess, Dragon's Rage Channeler's surveil, Slickshot Show-Off's pump, Cori-Steel Cutter's flurry). That makes Consign to Memory a strong answer, since it can replicate to counter multiple triggered abilities or colorless spells in one turn. Keep in mind it cannot hit their red or green spells like Lightning Bolt or Mutagenic Growth. Pyroclasm punishes their low-toughness creatures like Dragon's Rage Channeler (1/1 until delirium turns it into a 3/3), Monastery Swiftspear, and Slickshot Show-Off (both toughness 2), plus any Monk tokens from Cori-Steel Cutter. Cast it when they can't pump in response with a prowess trigger or Mutagenic Growth, and remember it also hits our own Psychic Frog and Emperor of Bones. Spell Snare snipes their two-mana spells like Cori-Steel Cutter, Expressive Iteration, and Slickshot Show-Off. Quantum Riddler and the slower, clunkier Persist copies come out since this matchup is a race where we need to interact rather than durdle. Thought Scour is a low-impact cantrip here, and milling the opponent could even help turn on their Dragon's Rage Channeler delirium.