Terrageddon wants to Armageddon away the board after setting up Treetop Village and Terravore, so cheap removal for their threats matters more than discard since much of their deck is lands and enchantments. Vendetta and the extra Diabolic Edict give us more answers to Terravore and Werebear/Wild Mongrel. Graveborn Muse's life loss is risky against a deck that can Armageddon and grind, so it sits; keep Wasteland and Mishra's Factory, since denying their mana base and racing with resilient threats is key after an Armageddon.