System-wide Replacement Macros:

{{user}} - your current Persona username
{{char}} - the Character's name
{{input}} - the user input
{{time}} - the current time
{{date}} - the current date
{{idle_duration}} - the time since the last user message was sent
{{random:(args)}} - returns a random item from the list. (ex: {{random:1,2,3,4}} will return 1 of the 4 numbers at random. Works with text lists too.
{{roll:(formula)}} - rolls a dice. (ex: {{roll:1d6}} will roll a 6-sided dice and return a number between 1 and 6)