This guide belongs to Dulfy. All credit to her, you can visit her website for the original guide: dulfy.net
GW2 Elon Riverlands Mastery Insights Guide.
Guide is organized such that the masteries requiring the least mount masteries are at the top while those requiring the most are at the bottom. Two of the insights require skimmer mount, one requires springer high vault and one requires jackal shifting sands mastery.