From B Nomic
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Append the following to rule 1-4:
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Player names must consist of between 1 and 64 characters from the
following list:
* Letters of the alphabet
* Underscores (_), dashes (-), or apostrophes (')
* Decimal digits
* Spaces
For the purposes of identifying players, and determining uniqueness of
names, the following conventions are to be used:
* Uppercase letters are to be considered equivalent to their lowercase
counterparts, and vice-versa.
* Sequences of one or more consecutive spaces are to be considered identical.
* Leading or trailing sequences of spaces may be disregarded or introduced.
Where a player's name might be ambiguous with other grammatical forms,
it may be surrounded by double quote characters (") to differentiate
it from surrounding text.
}}
Should any player names remain which are illegal or non-unique
according to rule 1-4, the Administrator shall change them to new,
unique, legal names, as determined by the guidelines in rule 1-4.