Hydroblast is the premier upgrade: it counters any red spell (Fiery Temper, Lightning Bolt, Lava Dart) or destroys any red permanent (Kessig Flamebreather, Guttersnipe, Voldaren Epicure) for one mana, directly shutting down their damage engine. Abandon Attachments is too slow and card-disadvantage-neutral against a deck racing to kill you by turn 5-6. Suffocating Fumes only grants -1/-1, which fails to kill Kessig Flamebreather (1/3) or Guttersnipe (2/2) and is not worth a slot here. Keep all removal (Snuff Out, Cast Down, Agony Warp) and counterspells online since answering their engine pieces before they trigger is the win condition; Snuff Out is especially strong since you'll usually control a Swamp-producing land and can pay 4 life to kill Guttersnipe or Kessig Flamebreather at instant speed.

Hydroblast and Blue Elemental Blast are premium here, countering or destroying red spells and permanents like Kessig Flamebreather and Guttersnipe outright. Nihil Spellbomb strips the graveyard to shut off Fiery Temper's flashback-adjacent recursion window and slows Faithless Looting's card selection, though it does nothing to stop madness casting since discarded madness cards go to exile, not the graveyard. Abandon Attachments and the clunkier creature-based cards come out since this matchup is a race decided by cheap interaction, not big bodies. Prioritize tempo: countering or blasting Guttersnipe and Kessig Flamebreather on sight denies their damage engine before it snowballs.

Hydroblast has no legal targets against Dimir Control since they run no red spells or permanents, so it stays in the sideboard — this is a near-mirror where the existing 75 is already well-configured. There is little profitable to bring in since Steel Sabotage and Annul have no artifact/enchantment targets in their list either. Marginally trim slow value cards like Abandon Attachments for nothing, since this matchup rewards keeping the exact counterspell and removal suite already built to fight over card advantage. Given the lack of meaningful swaps, keep the plan minimal and focus on sequencing Counterspell and Snuff Out to protect your own threats like Tolarian Terror.