Stiflenought is a glass-cannon combo-tempo deck with almost no blue permanents worth Pyroblast outside of resolved spells, but countering their Gush, Impulse, Portent, or Counterspell on the stack can buy a crucial turn. Our fast Mongoose/Terravore starts already punish their light removal suite, so the plan is to race rather than interact with Phyrexian Dreadnought directly (Wasteland has no targets against their basic Islands, so don't count on it for pressure). Devastating Dreams is a risky fit here: each player sacrifices X lands, which can hurt their mana, but the X damage to each creature also hits our own creatures and won't kill a 12/12 Dreadnought unless X is enormous, so use it as land destruction rather than a sweeper. Keep Lightning Bolt in to finish them off. Unearth is weak here since it is a slow sorcery that can be countered and needs a creature already in our graveyard.

Replenish's entire game plan hinges on resolving Opalescence with Parallax Wave or Decree of Silence, and Duress strips Attunement, Replenish, or a counterspell from their hand before they can set up the combo. Mind Harness stays in the sideboard: it can only enchant a red or green creature, and none of their permanents are red or green, so it has no legal targets in this matchup. Mulch is cut since there's no value in filling our graveyard against a combo-control deck we need to disrupt proactively instead. Wasteland remains important against their Ancient Tomb and Adarkar Wastes to slow their fast mana into Replenish.

Terrageddon shares our Terravore/Wasteland land-destruction gameplan but adds Armageddon to lock us out after they've established board presence, so this becomes a race decided by who disrupts mana first. Naturalize gives us flexibility against their artifacts and enchantments: Sylvan Library and Mox Diamond are the best targets, and it can also hit Seal of Cleansing (though they can sacrifice it in response) or an animated Mishra's Factory, which is an artifact creature until end of turn. Treetop Village is a land, so Naturalize can't touch it. Unearth is weak here because it can only return creatures with mana value 3 or less from our own graveyard, which is slow and situational compared to proactive mana disruption. Keep the full Wasteland and Devastating Dreams suite, since both decks are fighting over who can out-Armageddon the other with Terravore as the premier late-game threat.