[spoiler]PCs are immune to FIXED DC diplo, but so are any NPCs who actually get to talk. What I'd like to do is an opposed check of sorts, and the result should influence the behaviour of the loser - but he doesn't have to bend over backwards, and he won't suddenly change his ways entirely. I want to use Diplomacy as an indicator, not really as a resolver, because the mechanic is just too limited. So basically it's Diplo vs. Diplo when opposing choices are being discussed, or diplo vs. sense motive when it's just about convincing another person to take certain actions. Again, the mechanic is weak, and it should never result in a loss of control over a character - or an NPC, for that matter.
So as you correctly did, Torgthen's reaction should be a bit more favourable than without the check.[/spoiler]
The drow gave a short laugh.
'I have no problems with telling you anything and everything about my former people. I'm a drow, loyalty gets bred out of our system.
Good, where do I start: The Sisters have been transforming babies in the temple of Lolth. When they grow up, which they do rather quickly, they turn into real brutes who can snap necks with their bare hands. And they've been creating Driders like that, too. And finally... I think they've been mating with demons, too. What happens then... I don't know exactly. We were a small clan, but the sister want to expand, I think.
As to the Deep Dragon, his name is Axharolyx, he has a lair near here. He is a huge, scaly thing, and is doing the dragon thing: He is sitting on his pile of gold. I think he doesn't like leaving his lair, or else he would hardly have needed us to capture the celestials. I.... don't think you can win against him, but then what do I know.'
He relaxed again.
'Anything else you would like to know?'