Black Market Connections Black Market Connections is such a nice way to convert life into resources every turn, and with typal decks you can get a 3/2 changeling creature every turn
Other commanders care about this sort of thing, too
Being able to be such a disruptive one-unit army that forces opponents to interact with you on a different axis is fairly difficult, and there are a handful of games where Karn helps you interact with your opponent in exactly the right way by grabbing the artifact best-suited for the situation
If you're thinking of trying out this format, there are quite a few banned cards: Balustrade Spy Bloodstained Mire Expressive Iteration Felidar Guardian Field of the Dead Flooded Strand Geological Appraiser Inverter of Truth Karn, the Great Creator Kethis, the Hidden Hand Leyline of Abundance Lurrus of the Dream-Den Nexus of Fate Oko, Thief of Crowns Once Upon a Time Polluted Delta Teferi, Time Raveler Undercity Informer Underworld Breach Uro, Titan of Nature's Wrath Veil of Summer Walking Ballista Wilderness Reclamation Windswept Heath Winota, Joiner of Forces Wooded Foothills MTG Historic banlist Historic is a digital format for MTG Arena, and is the app's largest constructed format, consisting of both old and new cards
Three more experience counter commanders have been printed in Kelsien, the Plague, Minthara, Merciless Soul, and Otharri, Suns Glory, making a silly experience counter theme deck possible
