1) Take the teleport in the violet citadel to the purple parlor
2) Mount up
3) Fly down to the alliance area
4) Fly through the door and land in the middle of the staircase and you won't be teleported out
5) Walk onto the edge of the stairs and you can follow the ledge around
6) The battlemaster spawns under the marked arrow and can be killed. You can walk up to about the area marked on the ground before you get teleported out