So I'm currently at this quest with my main character, which is an air/water mage. Since one of the opponents is immune to physical damage while the other is immune to magic damage, does this mean I have no other option but going back to the Lady Vengeance and rebuild my champ as a hybrid character because the quest is impossible to do?
As a physical champ I could toss grenades or as a ranger, shoot elemental arrows to deal with the physical resistance opponent, but as a mage I seem to be royally screwed on this. Who thought this was good quest design and how drunk was the team when they implemented it into the game? So much for identifying with your game character when you are forced to rebuild it because of bad quest design...
edit: excuse the double post, GOG galaxy bugged out and it seems they did not implement something as fundamental as being able to delete own posts...
Are you playing with just one character? Otherwise your post doesn't make sense for a couple of reasons. First there is a healthy variety of ways to accumulate your source points--don't think there are "only three" because there are not (I counted 5 or 6 source-point quests that I undertook--but of course you only get three points total--the others give you more XP and a variety of objects, etc.) There may be more--but didn't wait to find out...;) So if you have to then take another quest for your third source point. I also did the ritual three times as you talk to your God every time and he will give you some neat abilities and other things as well after the ritual.
So, in your fight you speak of immunities...you kill one of them with physical damage and one of them with magic damage. Your character(s) should easily be able to do that while having some fairly robust physical and Magic armors, etc. How is it "bad design" if you choose to develop your character's intelligence at the expense of his strength--that's your choice--has nothing to do with the quest design. Especially if you are playing with a single character!
Getting three source points is actually easy *if* you have your characters balanced instead of lopsided...;) The recommended game method is with four players--I have a fighter, a rogue, a ranger and a pure mage. I mow them down now...;) Playing with a single character if that is what you are doing is your decision as opposed to the game's, as the game and the quests were designed for four characters. All my characters have ranged attack skills of some kind, and my fighter does both (he has almost all the warfare skills.)