It is recommended to take out Barnabas first, as he will self-destruct should Dr. Lugae fall before him - if this happens it will deal an amount of damage equivalent to however much HP Barnabas has remaining. There will be a short interval until Barnabas starts attacking the party, as he directs his first attack at Lugae, so this is a good time to shore up the party's stats with Haste and/or Shell; one can also inflict status ailments on Barnabas, although Lugae will probably end up removing these after a short while. Cecil and Yang should attack while Kain uses the Jump command. Rydia should use Black Magic or Summon, whichever is more MP efficient. While Rosa is not healing the party, she can add some damage with physical attacks and give a few good status effects to the party. Occasionally Lugae will say something about oiling Barnabas, and heal him for about 500 HP while also removing any status ailments he is afflicted with. After Barnabas is defeated, Lugae will take control of him, who now becomes Barnabas-Z.