Mono-Green Eldrazi's early creatures like Fanatic of Rhonas and Disciple of Freyalise survive a base Unholy Heat, but once delirium is active it scales to 6 damage, easily handling those creatures. It won't be enough to destroy their biggest Eldrazi threats like Ulamog, the Ceaseless Hunger or Emrakul, the Promised End, but those are slow to arrive and easier to race than to answer. Surgical Extraction can disrupt redundant copies of key pieces found via Green Sun's Zenith or Malevolent Rumble, denying recursion. Their removal suite is light, but games can go long as they ramp into their expensive top-end, so combat tricks like Monstrous Rage and Assault Strobe are less valuable than proactive removal and pressure. Race aggressively before they reach their biggest threats.

Boros Energy's sweepers, Wrath of the Skies and Avengers Disassembled, are the biggest threat to our board, so Spell Snare comes in to counter their two-mana spells like Cleansing Wildfire and Price of Freedom, while Unholy Heat cheaply answers Solitude and other small creatures, scaling with delirium against bigger threats. Their abundant removal (Path to Exile, Solitude, Galvanic Discharge) punishes combat tricks that don't affect the board, so Monstrous Rage and Assault Strobe are cut for more resilient interaction. Play around their land destruction package (Cleansing Wildfire, Field of Ruin, Demolition Field) by not overextending mana, and race to close the game before Wrath of the Skies resolves.

Affinity's board is full of cheap artifacts, so Meltdown can wipe out Mishra's Bauble, Mox Opal, Welding Jar, and low-mana-value artifact creatures for a well-chosen X. Consign to Memory counters colorless spells like Engineered Explosives outright, which is huge disruption against their artifact-based game plan. Their deck lacks efficient creature removal outside Engineered Explosives, so Monstrous Rage and one copy of Assault Strobe are cut since resetting their board with Meltdown matters more than pushing extra damage through their sweepers. Diversify the mana values of your threats to play around Engineered Explosives.