jeregenest

But your creating Fancy, thought it fit
To make your World of Nothing, but pure Wit.
Your Blazing-world, beyond the Stars mounts higher,
Enlightens all with a Celestial Fire.

—The Duke of Newcastle, upon the publication of his wife Margaret's The Blazing World (1666), arguably the first alternate reality story in the English language.

In this Lexicon the players will take on the role of an individual associated with the concept of alternate/parallel worlds in a cross-time milieu. The game will be played in 9 turns, each based on a range of breakpoints, moving backwards in time. The turns will consist of the following eras:

1939 to today
1850 to 1938
1700 to 1849
1300 to 1699
500 to 1299
100 BC to 499AD
600 BC to 100 BC
1200 BC to 600 BC
Pre-1200 BC

1. On the first turn, each player writes an entry for a world that diverges due to events in the covered time period. You come up with the name of the entry, and you write about the world. Each entry should cover, at a minimum, the following: A point of change from the history of our world that takes place in the covered era; a change which would alter history as it is known; and an examination of the ramifications of that change. At the end of the article, you sign your name, and make two citations to other entries in the encyclopedia. These citations will be phantoms -- their names exist, but their content will get filled in only on the appropriate turn. No era can have more entries than the number of players, either, so all citations made on the first turn have to start with breakpoint eras before the modern (i.e., subsequent turns).

2. On the second and subsequent turns, you continue to write entries for the era covered in that round. However, you need to make three citations. One must be a reference to an already-written entry, and two must be to unwritten entries. (On the last two rounds, you only need to cite one and zero phantom entries, respectively, because there won't be enough phantom entries, otherwise.) Please note that both new and already existing phantom entries (i.e. ones that had already been cited before) count toward the two you must cite.

It's an academic sin to cite yourself, you can never cite an entry you've written. (This forces the players to intertwingle their entries, so that everybody depends on everyone else's facts.) Incidentally, once you run out of empty slots, obviously you can only cite existing phantom slots.

3. Despite the fact that your peers are self-important, narrow-minded dunderheads, they are honest scholars. No matter how strained their interpretations are, their facts are accurate as research can make them. So if you cite an entry, you have to treat its factual content as true! (Though you can argue vociferously with the interpretation and introduce new facts that shade the interpretation.)

I think this covers the basics. Does it work for people? Any questions? I basically adapted standard lexicon rules and came up with some interesting looking eras. Everything is open for debate.