I just got to the 4th level and this message appeared-
Davaeorn - Protected from Normal Missiles.

And I wasn't even NEAR davaeron! He wasn't on my screen or anything! Why does the game do this?!?!

It's a good thing. It's the game letting you know that he cast that spell. If you listen, you can hear the humming of it anyway. It's that pink cylindracal field around him. It does it all the time in BG2, when everyone is casting spells all over the place.

Where's the entrance? I didn't see it.

The entrance to what? The 4th level of the Mines? It's in the east corner of the southernmost room of the 3rd level.

Davaeorn's Protection from Normal Missiles is NOT like the spell--it will not wear off, and if you Dispel it, leave the level and then come back, it will pop back up again, along with his Mirror Images. Not that that's going to make Davaeorn a tough fight, what with Yeslik being right there if you need him....

Since the designers probably thought fighting Davaeron would be too easy if you could just fire unenchanted missiles at him he got the protection spell. It activates immediately because, unlike in BG2, there are no spell contigencies or triggers. That means that without the auto-activation the mage would have to begin by casting that spell, leaving him open to normal missiles and spell disruption for a few seconds. Making him a rather easy target.

Oh, and it does work like a spell, but one with extended duration. If the fight is too hard for you, try entering Davaeorns level and resting for eight hours. The protection will have worn off and you won't have much of a fight left ;)

There's no actual reason why you should or should not get to see the message and learn he is protected from normal missiles, but it is useful information as you'll know to equip missile troops with magic projectiles for the fight.

We can add this to the discussion. Even though you could not see him, tramping around in steel armor and killing everything along the way probably made a wee bit of noise. As he hears you get closer, he casts his protection spell. Of course he still does it if your thief is hiding in shadows and tries to sneak up on him. ;)

Hrm, ok, how do you beat this guy? I saw that pink ring thing he had around him and stuff and he cast Dire Charm on me and I had heard that Dispel would get rid of that stuff so I had to trek all the way back to that area just north of the gnoll fortress to get it...is this all I need?

And what do you do if you've got an all fighter party? He can't be touched by my fireball spell without dispelling anything...

Fire some magical arrows +1, +2, or magical bolts +1, +2, or magical bullets at him. He's only protected from normal missles.

The problem I found is that the computer doesn't reveal enough about what's going on. For all I know, my Arrows +1, or Arrows of Biting aren't even doing any damage to him, as the stats never ring up on the dialogue screen. As for his mirror image spell, if you rest, the thing is still there. It most certainly doesn't follow the prescribed rules for its duration.

Like all spellcasters, you have to disrupt his casting. Magic Missles are the best for knocking off his images and disrupting his spells. The toughest part of this fight is his chicken s*** Dimension Door. Don't go running around after him. Stay at the intersection in the middle. He always materializes within sight of the intersection. Nail him with MMs and ranged weapons and don't charge him.