The expensive one. A long quest chain across every Path of Fire map, and a bill at the end of it.
The griffon is not sold and is not a collection you can start on day one. It waits on the Path of Fire story being finished, opens into a chain that sends you across all five of the expansion's maps, and closes with a substantial gold cost. Budget for it before you begin rather than halfway through.
Complete the Griffon Training adventure in the Domain of Vabbi to unlock the Griffon Mastery Track.
The griffon rewards the mastery track more than any other mount: untrained it is a glide with extra steps, and fully trained it is the fastest way to cross a map in the game.
