https://warcraft.wiki.gg/wiki/API_SecureCmdOptionParse
/run local t={0} if not SecureCmdOptionParse("[advflying] [flying]") then t={2339,663,1825,682,404,1943,311} end C_MountJournal.SummonByID(t[random(#t)])
If the zone doesn’t support flying pick from the list, otherwise do random.