What exactly are 'one-time use' tags, and what can I use them for?
one-time-use tags are special tags that are automatically allocated each time you mark an NPC as usable only once.
When you use the NPC, the NPC will be removed from the map, and the usable only once tag will be turned on. The most common use for one-time-use tags is to turn an NPC into a treasure box.
[edit] Manually changing
Warning! This is a bad idea! Don't do this!
It is theoretically possible to manually change an one-time-use tag using plotscripting and the set tag command, but this is a bad idea, because backwards compatibility might not necessarily be guaranteed in the future when the number of available tags increases
[edit] How else can I do this?
If you are going to want to manually manipulate your one-time-use tags, then it is much better to just use a regular tag instead.
Name a tag. Then make the NPC only appear if it is OFF. Then edit the text box which is displayed when you activate the NPC, and in the "conditionals" screen, make the tag turned ON
