I just beat that encounter not too long ago. It helps if you split the party and put the strongest character you got, preferably melee at the top of the rigging to take out the aero and swash that come up there, or you can use teleport if you have more than 1, 1 is good too, and bring them to you. it was annoying at first but you just gotta stay back near the entrance to the encounter and bring them to you. After you kill some skeletons the boss will just teleport on top of your party and he's really not that strong.
Last edited by Kokoro-Sensei; 15/09/16 11:52 PM.