Lexicon is a game of roleplaying and collaborative world building, in which players write the (fictional) history and background of a particular (fictitious) time, place or incident.
From an in-character perspective, you're probably an irritable, opinionated scholar, with a theory for everything. Which is fine - the pompous fools that laughably call themselves your colleagues are, for the most part, also irritable, opinionated scholars with theories for everything. Together, you compile an encyclopedia or guidebook or such - a complete fictional reference on your topic.
We're starting with out characters compiling a guidebook on the city of Falkensburg. Falkensburg is a Steampunk/Fantasy city with a most curious property - there seem to be portals that lead to other places, other places about which they'll doubtless have to collectively write.
As we're playing it here, a game of Lexicon lasts for thirteen turns, with each turn running for one week. One turn runs from 1200 UTC on Friday until 1159 UTC the following Friday.
At the start of a turn, two letters will be designated for the week - for example, A and B, or E and F, or P and Q - and each player must write one article for each of the letters. Letters will be designated in order.
Toward the start of the game, an article can be about anything, provided the name starts with that letter. Later on, if there's already a phantom article starting with that letter, then players must write for the established phantoms instead of making up one of their own.
After a player submits an article, they may choose one article for the next turn to claim authorial rights on. After submitting your second article for the turn, you may claim a second article for the following turn. If the phantom limit has not yet been reached, they may choose to create and claim a new phantom for the following turn. Otherwise, a player may claim an existing phantom article. To claim an article, simply leave a note on it stating that you are claiming it for the next turn.
In regards to naming conventions, use the first letter of how the full name would be written, ignoring any titles or articles. This means that "General Bob Jones" and "The Blowfish Cafe" are both filed under "B".
The exception to this is the letter 'X'. In turn 12 (W, X), the 'X' is treated as a wildcard letter. Articles created for 'X' may begin with any character the player desires.
Articles should be at least 150-200 words, should be signed by the player's character. For turns 1-11, articles must cite two nonexistent, 'phantom' articles later in the alphabet as references. Additionally, for turns 3-13, each new article must cite at least one previous article. An article may be about anything (within a very broad definition of reason), provided it doesn't contradict previously established 'facts'.
When citing a phantom article, players should create the article in question, but leave it blank or with a brief note explaining what article created the phantom. Players are free to cite any other articles they wish above and beyond the required three, but may not create more than two phantoms per article.
If a player can't write complete entries in a given turn, they may post stub entries to be completed later. Stubs must meet the same link requirements as complete entries, but are subject to the tender mercies of 'facts' that are established later.
When linking to phantom articles, they don't necessarily have to be completely new. Players are free to link to phantom articles that already exist - and, indeed, are required to when no new phantom articles may be created. If you link to a new phantom article, you must create the page for it to act as a placeholder until such time the article is written.
If, at the start of a turn, the number of phantom articles for a given letter is more than the number of players, no new phantom articles may be created for that letter. Administrators will make note of this on the LJ community when this event occurs.
Additionally, no new phantom articles may be created at all if there are enough already defined to occupy all the players for the rest of the game. If this happens, then players must link to already-defined phantom articles in their entries.
It's an academic sin to cite yourself. This being the case, players can never directly cite any entry that they've written. In practice, this rule ensures that players will reference each other's entries.
Citing another player's entry that cites one of yours, on the other hand, is academia fair game.
Fact is Sacred, Comment is Free
Your colleagues are idiots, unable to see past their own monocles. That said, they're also honest idiots.
What this means is that all previously-established 'facts' are perfectly true, and an article isn't allowed to contradict the factual content of any article(s) that it cites. This means you will have to do your research.
On the other hand, players are free encouraged to argue with the interpretations and inferences their colleagues make. This can be done in one of two ways - either by (a) writing new articles that set the record straight, or (b) arguing it directly on an article's discussion page.