This mono-green landfall deck is almost entirely creatures and lands, so Day of Black Sun is a full creature sweep that strips abilities before destroying, shutting down creature landfall payoffs like Mightform Harmonizer. Flashfreeze counters almost every spell they cast, making it excellent proactive interaction against Icetill Explorer, Earthbender Ascension, or Mightform Harmonizer. Nowhere to Run's -3/-3 is too small against their bigger threats and We Say Thee Nay! is too slow against a deck that just wants to jam threats and grow them, so both come out. Ghost Vacuum also helps interact with any graveyard-based value from Icetill Explorer's land recursion enablers.
This is a mirror-adjacent matchup against another Dimir deck built around Doomsday Excruciator and graveyard value, so Duress is premium, stripping their removal (Bitter Triumph, Requiting Hex) or Day of Black Sun before it lands. Strategic Betrayal forces them to exile a creature they control along with their graveyard, denying any Superior Spider-Man mind-swap targets and Winternight Stories harmonize fuel. Shoot the Sheriff, We Say Thee Nay!, and Nowhere to Run are cut since their creature base is small and low-impact compared to proactive discard and exile effects that attack their card advantage engine directly. Keep Bitter Triumph in since Superior Spider-Man and Doomsday Excruciator are both worth killing.
Duress can strip High Noon before it locks down your ability to interact each turn, or take a key spell like Avatar's Wrath before it resets your board. Disdainful Stroke answers Avatar's Wrath or Enduring Curiosity's high-value casts. Nowhere to Run's single-target -3/-3 struggles against Voice of Victory's token swarms, and We Say Thee Nay! is a bit slow against their tempo-oriented flash creatures, so both are trimmed for proactive answers. Keep Requiting Hex and Bitter Triumph in as they efficiently answer Voice of Victory, with Bitter Triumph also hitting Aven Interrupter and Skycoach Conductor.
Suggested new sideboard cards to pick up for the current metagame.
Missing sideboard cards? The full 15-card sideboard runs about $27.41.
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