All guilds ~should~ be roleplaying, just like all characters ~should~ be roleplaying. The ones that don't roleplay tend to die out pretty quickly after mass recruiting up to 150 players. The Guild Knights were a good example of that... the only roleplayers were near the top of the ranks, and even then it was pretty sketchy, and the guild was huge. Now it's gone except for maybe one guy who I think finally left not too long ago.
I think the best way to find out about guilds is by asking in game and in character. You'll have more fun that way, and you might get more colourful responses. The prophets of chaos are a slightly insane bunch. They don't see themselves as evil though. A lot of their members are rather juvenile but I think they have potential and a sincere interest in roleplaying. There's also Culmi Navarre, but if it's membership you're interested in you're probably out of luck. (Culmi Navarre is one of those "Don't come to us, we'll come to you" deals on some level.) There have been other guilds that have come and gone but still have a legacy of sorts. Verrliit Razorclaw used to be in a guild called "Twin Blades of Arete". They were relatively evil and more than just a bit fanatical. They had this weird fascination with perfection and killing things. She's still active and might have an interesting thing or two to tell you.
