Selesnya Company floods the board fast with Elvish Mystic, Llanowar Elves, and Collected Company hits, so Iroh's Demonstration's 1-damage-to-each-opponent-creature mode is excellent against their mana dorks and small creatures like Enduring Innocence. Ashiok, Dream Render shuts down their Collected Company/Formidable Speaker-style card selection reliance on searching and can exile their graveyard, while Octopus Form protects a key threat from Skyclave Apparition or Get Lost. Wild Ride and This Town Ain't Big Enough are too slow and reactive against a deck that wants to overwhelm the board quickly, so they're cut for proactive removal and disruption. Watch out for Archon of Emeria limiting you to one spell per turn, and sequence your interaction accordingly.