There's currently 106 obtainable factions in the game (+2 removed), with Shadowlands looking to add at least another 4 at launch for a total of 110+2. Although there's not yet a 110 faction achievement on the beta, I'm hoping this'll be amended before the release of Shadowlands, although I'd not be surprised if they held off on it until a later date...
ANYWAY!
What'd you like to see from such an achievement? Any titles in mind? Another mount? What do you think would be a fitting reward?