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Random Encounters based on passages
I've been playing around with the code form Dan Cox's tutorials 
and I've got it to where a player could advance from one room to another, but I'm having trouble getting the "Grue" event to only run when on the "init" passage.
and I've got it to where a player could advance from one room to another, but I'm having trouble getting the "Grue" event to only run when on the "init" passage.
Comments
The init passage (0:48) in his example is used to setup the default values of all the $variables. Normally the way to do this in SugarCube is to create a special passage named StoryInit and to place the code to initialize your $variables in there, this special passage is automatically read at the start of your story so you do not need to <<display>> it (1:13) within your story's first passage.
His statement that SugarCude does not have a random macro (6:45) is not fully correct, it does have a random function.
His init passage does not directly causing the Grue event to happen as all it does is initialize the $attackNumber variable.
The Grue Attack event is triggered by the random chance code within the Grue passage (6:06) and by the Grue passage being displayed by the <<display "Grue">> (8:52) within the Map System passage.
So the Grue attacks wont happen until all the related coding has been done, which is around (11:30) in the video.