Yes i finished this part recently.

It is VERY hard.

Here is how i did it:

Look at the map just outside the Maze (press pause). Do you see 2 lanterns/posts on the ground? There is one beside the rear of the Airship.

This is yuor rally point. If you see closely you can see that this area can be used as an effective blockage so that only your fighters suffer melee attacks.

What you need to do is, stuff your mages in there first then block the entrance with you fighters. Cast as many cleric spells as you can and while you fighters hold off the attack, use mage spells like Fireball, Magic Missiles to kill off the monsters.

It is also useful to summon.

Another tip, for some reason Harpies get killed easily by a well placed Skull Trap spell.

The most important part is to find the place i am talking about. (just right of the door you came out of).

Hope this helps.

Good luck mate.

Lol derf read my post again. I said i finished the fight from my first try without any decent cleric- and/or magespells.