Unlike Normal and Heroic difficulties, Argus' Mythic version has secret phases that aren't detailed in the in-game Dungeon Journal or spoiled on the test server. When famous guilds like Method stepped into his arena for the first time, they were doing so completely blind. At that time, Method was the first guild to fight Argus but eleven others have since caught up. While Method is still expected to kill him first thanks to their rigorous raiding schedule, it's anybody's game at this point.