Under the current rules (as of writing this blog post) both of them would simply die as a state-based action due to the planeswalker uniqueness rule, so nothing special happens
2023-11-10 Any choices made when the ability resolves won't have been made yet when it's copied
Marvels Spider-Man NEWS Under the Mask with Magic: The Gathering | Marvel's Spider-Man Creative Design Join Aaron, a senior narrative game designer, for the story of how Magic combined comics with cards in this amazing, spectacular, and friendly set
Julius Jumblemorph Ego Erasure Feisty Spikeling Firdoch Core Fire-Belly Changeling Flock Impostor Formless Genesis Game-Trail Changeling Gangly Stompling Ghostly Changeling Gladewalker Ritualist Graveshifter Guardian Gladewalker Impostor of the Sixth Pride Irregular Cohort Littjara Littjara Glade-Warden Littjara Kinseekers Masked Vandal Maskwood Nexus Mirror Entity Mischievous Sneakling Mistform Ultimus Mistwalker Moonglove Changeling Moritte of the Frost Morophon, the Boundless Mothdust Changeling Mutable Explorer Nameless Inversion Omni-Changeling Omo, Queen of Vesuva Overlord of the Hauntwoods Personify Prideful Feastling Realmwalker Rooftop Percher Runed Stalactite Shapesharer Shields of Velis Vel Sizzling Changeling Skeletal Changeling Springleaf Parade Stalactite Dagger Taurean Mauler Three Tree Mascot Turtleshell Changeling Universal Automaton Unsettled Mariner Valiant Changeling
Paragon of Eternal Wilds, Hunter's Ambush, and Sylvan Anthem each take advantage of your many green creatures
