How do I defeat Omega in the Lifespring Grotto in Final Fantasy I: Dawn Of Souls?

Okay first of all this is an OPTIONAL boss fight. Du have to let me know the lineup for your party. When I did it I had Knight, Ninja, White Wizard, Red Wizard all around level 60. Try to reduce the wave kanone damage Von casting protect and shell...maybe haste on a few characters. USE CURAGA EVERY TURN. Hope this helps. :D