"Lock and Key: Variable": SugarCube (v2.18)
"Lock and Key: Variable" demostrates how to create the effect of picking up a key and unlocking a door. In this example, the key is a variable ($key) and is initially set to the value false in the Start passage.
When the link (created using a <<linkreplace>> macro) "Pick up the key" is clicked, $key is changed to the value true and the door link changes from its initial response of "Locked Door" to a link to the passage Exit.
:: StoryTitle Lock and Key: Variable in SugarCube :: Start <<set $key to false>> Rooms: [[Back Room]] [[Front Room]] :: Back Room <<if $key is false>> Items: <<linkreplace "Pick up the key">><<set $key to true>>You have a key.<</linkreplace>> <<else>> There is nothing here. <</if>> Rooms: [[Front Room]] :: Front Room <<if $key is true>> [[Exit]] <<else>> Locked Door <</if>> Rooms: [[Back Room]] :: Exit You found the key and went through the door!
Download: Twee Code