The best Madness cards are ones you want to cast already and are fine in your deck
Chances are, dropping either one of these early will delay the Zenith player a few turns, which should be all you need to win
It seems silly to have to convince people that the newest iteration of Attune with Aether and Traverse the Ulvenwald is playable, but here goes Imagine that Flower is effectively a Selesnya Guildgate
Charix, the Raging Isle + Ragost, Deft Gastronaut Charix, the Raging Isle and especially Ragost, Deft Gastronaut are not really scary, but if you have a phobia of crabs or lobsters, you want to scroll past this
Paired with cards like Soul Warden and Soul's Attendant, players can even immediately gain that lost life back and create an immense army of soldiers
Commander players, get ready for some curtailed games next time you face mono-green