I am releasing a beta of the combat system. Right now it deals random damage between 0 and 9 whenever you attack, when I get back in a couple of hours I will implement the damage formula, THAC0 and AC.
Please, try it out, and post your suggestions etc. If you find a bug, please post about it, would be great if you could explain how it occurs.
To duel someone, say:
/duel <charactername>
For example "/duel Ziro". You have to wait for the other player to accept the duel, but if it isn't accepted within 60 seconds, it will time out and cancel the duel request.