Good little game. I used a Paladin and Mage and found it very straight forward. The paladin is basically pretty good with mele and magic and its healing ability helps to support the mage with its low health. Both character types also have good abilities for taking on individual units and for attacking groups of opponents. Use this combo if your really stuck!
The way to beat the last boss is to fly past quickly and shoot the hell out of it then fly away and destroy all the small fighters. Hopefully once you destroy a couple of sections of the boss it will drop missile producing upgrade which just keeps producing missiles. Then just repeat by blasing with missiles and retreating.
Ok game but too mcuh luck involved, more games with the Cthulhu Mythos please. Oh and for the people who think this is satanism it isnt, look it up and read H.P Lovecraft.