I am wondering if the achievement for the mythic 15 and the mount can be obtained by doing all the dungeons but on different characters or you need to have one character do all 15 in time ?
I was thinking of splitting on different characters but of course need to be sure
Wowhead says its accountwide progress.
“In the new PTR build, Blizzard has changed the Keystone Master and Conqueror achievements, to complete all Mythic+ dungeons in +15, to be account-wide. This change means that you can complete each dungeon in a separate toon and still complete the achievement.”