The Basic Rules
This should be pretty familiar. They're what you probably learned at home growing up: Keep it civil, keep it clean, and keep it on topic.
I don't think these are things too great to ask of you when you come to the forums, as you are essentially stepping into our 'home' on the web. Just as you'd be civil in a home you are a guest in, I ask you to be the same here. I know being online leaves you great anonymity - but come on, really, there's no actual need to prove anything is there?
That means that we'll try to give you the benefit of the doubt as you post. Context matters. Tone matters. And these rules can't possibly cover all the situations that may arise. We'll make judgement calls if we have to.
Our job is to watch over the forums and keep fights, hot topics, and generic spam/junk down. We have to weigh the health of the community as a whole, and I do regret that we can't always make everyone happy. I really wish we could, but I found out a long time ago while admining on MUDs that that's impossible. We can't do it. Not and still be effective in what we do. By comparison I think you would find the rules on other forums of a simular nature to ours to be much the same if not identical.
(Credit to Eric of www.enworld.org for clarifying what the rules 'mean'. The following is paraphrased just a little.)
Keep it civil: Please don't engage in personal attacks, name-calling, or blanket generalizations in your discussions. Say how you feel or what you think, but be careful about ascribing motives to the actions of others or telling others how they "should" think. People seeking to engage and discuss will find themselves asking questions, seeking clarifications, and describing their own opinion. People seeking to "win an argument" sometimes end up taking cheap shots, calling people names, and generally trying to indimidate others. If you find yourself 'trying' to win, then chances are you're about to cross that line. Take a breath, and back off and think about it a little.
Keep it clean: Please try to keep the cursing low key and don't link to sites with inappropriate content. The "acid test" we use is the "Grandmother Rule" -- if it would be inappropriate to say to or show to our grandmothers, don't do it. I want a typical 13 year old kid to be able to come here and participate if they want to without feeling uncomfortable. This should be a minor-friendly place. Think about it this way: how do you act around strangers or work acquaintances? You watch your language and you're on your best behavior. That's the ideal we're shooting for here.
Keep it on topic: It's not that we actually forbid off-topic conversation. But keep in mind that this is a Planescape site, with many sub-forums on lots of related topics. Try to put your posts in the right forums and the right threads (it helps people find stuff, for one thing). In this category I should mention the "no religion, no politics" rule -- please refrain from discussion of a religious or political nature. This last may seem a rather draconic rule, but it has helped keep the peace around Enworld for a long time, and I'll exercise the right to do the same here. There are plenty of places on the internet where one could have those sorts of discussion.
What happens if I break the rules?
We may just email or private message you, gently reminding you about the standard of conduct we expect here; we may post in the thread or topic if we feel it will help; we may temporarily lock the thread for tempers to calm down and for review; alternatively, we may suspend your account, either temporarily or permanently.
The more complaints and problems you have accumulated, the less gentle we are likely to be. This is because we expect that after getting warned enough times, you really ought to know better and have learned something along the way. You don't have to agree with us, and we certainly can't expect to win you over on every subject, so you're free to discuss whatever you want elsewhere - here, we ask you to make an effort to follow the above guidelines.
Also, if you include a phrase such as "this will probably get me warned or banned, but..." in a post, then this indicates to us that you know you're about to bend/stretch/break a rule. That shows us you're pretty much sticking your fingers up at the rules and the admins, so we reserve the right to ban you. We certainly don't want to, but if you're wanting to ask for it that much we probably won't deny it to you.
Expanded Off Topic Rules
Expanding on the subject of "Off Topic" posts in Planescape: There are inevitably subjects that will come up again and again in Planescape. On the surface they are directly game-related, but in reality can cause such divisiveness and annoyance as to be not worth the trouble they cause. As should be expected, these are usually of the political or religious nature.
When we manage to bring these subjects to some form of informative conclusion, I will add them to the Forum Rules. They will be considered 'dead topics' thereafter, and further threads on these matters will be closed with a link to this FAQ and the relevant threads of past discussion.
Dead Topics
Does God exist in Planescape? What are God's stats?
* God in Planescape (Please don't light me on fire)
* Judeo/Christian/Muslim material in D&D/Planescape