Mono Red Madness wants to race with burn, so cheap interaction that kills their small creatures (Voldaren Epicure, Kessig Flamebreather, Guttersnipe) before they chain spells is key. Cut Down trades efficiently with all their low-toughness bodies, and the extra Grim Bauble's -2/-2 can snipe an Epicure or Guttersnipe on arrival before it does damage. Baleful Strix's deathtouch blocking matters less against a deck trying to burn you out rather than attack, and the third Giant's Boulder is too slow for this race. Keep the low curve and racing plan otherwise intact.

Dimir Control plays no red spells or permanents, so Hydroblast is entirely dead, and its Counterspell/Snuff Out/Cast Down-heavy removal suite isn't well answered by Envelop (which only hits sorceries, catching things like Lorien Revealed but missing their counterspells and instant-speed removal). None of our sideboard cards offer a clearly profitable swap against this grindy control deck, since Cut Down and Grim Bauble are already in the mainboard and the rest of our sideboard is color-restricted against red/blue-specific decks. The best plan is to keep the maindeck as-is and win by presenting more threats per turn than they have cheap removal, since Nihil Spellbomb-style graveyard hate accomplishes little against a deck without a graveyard plan of its own.

This is the mirror match, decided by who assembles artifact count and card advantage engines faster. Tithing Blade forces an on-entry sacrifice, a strong rate against their Kor Skyfisher, Glint Hawk, and Baleful Strix bodies, and the extra Nihil Spellbomb adds a cheap artifact for metalcraft plus a late card draw. Baleful Strix trades down against their own evasive fliers and a third Giant's Boulder is too slow, so both are trimmed for more proactive, cheap artifact density. Prioritize racing and using Dispatch's exile mode on their best fliers.