What's everyone's opinion about Karn, Scion of Urza's long term usability in Affinity. Is it a staple for the deck or just a one time champion due to its popularity in standard? :
Karn, Scion of Urza – CustomizedMTG – Magic the Gathering Proxy Cards
Traditional Historic - Karn Control (Video Guide)
Dominaria Playmat Karn, Scion of Urza for Magic, Ultra PRO