This mirror comes down to card advantage and resilient threats, so extra discard with Duress helps strip their Professor Dellian Fel, Unholy Annex // Ritual Chamber, or removal like Abrupt Decay and Fatal Push before they take over the game. Duress can't take creatures, so Sheoldred, the Apocalypse needs to be handled by your removal instead. Unlicensed Hearse can exile cards from graveyards, which shrinks the life drain from Graveyard Trespasser (it needs creature cards to exile) and takes away Takenuma, Abandoned Mire's recursion targets, while growing into a threat of its own once you have creatures to crew it. Culling Ritual is weak here since both decks curve out with resilient 3-4 mana threats and lands-as-creatures that dodge mana value 2, making the sweeper mostly dead. Fatal Push is still fine against cheap creatures and an animated Mutavault, but it struggles against Sheoldred and Sentinel of the Nameless City without Revolt active and can't touch Professor Dellian Fel, so trimming to two live copies while adding targeted discard is the better plan.
Izzet Cauldron is a grindy spells deck with few early creature threats, so Culling Ritual loses value and one Bitter Triumph can be trimmed, while Go Blank punishes their graveyard-fueled Eddymurk Crab discounts and strips their hand. Unlicensed Hearse adds pressure as a resilient clock while also exiling cards that discount their Crabs and feed Hearth Elemental. Keep Thoughtseize and Duress copies to disrupt their card-selection-heavy plan, and save the remaining Bitter Triumph and other removal for Sunderflock, Eddymurk Crab, and Hearth Elemental since those are the only real bodies they deploy.
Selesnya Company wants to flood the board with mana dorks and small creatures to power out Collected Company and Ouroboroid, so the extra Culling Ritual sweeps away Elvish Mystic, Llanowar Elves, Badgermole Cub, and Thalia, Guardian of Thraben in one shot (everything at mana value 2 or less) while ramping you back into gas. It will not touch Skyclave Apparition, Archon of Emeria, or Enduring Innocence, which all cost three, so save your spot removal for those. Go Blank makes them discard two cards from hand, which can take key cards like Collected Company or Elspeth, Storm Slayer before they get cast. Fatal Push loses value here: without Revolt it only hits mana value 2 or less, which Culling Ritual already covers, while their better creatures (Archon of Emeria, Skyclave Apparition, and Enduring Innocence at mana value 3, Ouroboroid at 4) need Revolt to be in range. Collected Company and Elspeth are not creatures, so Fatal Push can't answer them at all. Trimming it keeps the removal suite from overlapping with the sweeper. Keep Abrupt Decay's remaining copies and Bitter Triumph as your primary answers to Archon of Emeria and Skyclave Apparition, since those still hit everything in range.
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