According to this meta suggestion, single-use tags will no longer expire if they have a tag wiki.

We have a historic problem whereby users will ask about a game system (and a tag will be created for it), but that will be the only question on the system, dooming the tag to later be obliterated and, in a lot of cases, the context for the question will be lost. Help us save them!

What can you do to help?

Add system tags to the below list that only have one question and no tag wiki. Link its lone question as well, so that in the future the tag can be recreated and reapplied.

Rescue tags on the below list by either proposing a tag wiki, asking another question with that tag, or tagging another question about that system with that tag. If the tag's been destroyed since, add it back to the linked question if and when you can also rescue it through one of those actions.

If any of the below tags ought not exist, remove them from the question so they can be obliterated.

Remove tags from this list when they're safe (or deliberately obliterated). Please note in the edit summary what you did exactly ("created a wiki", "tagged another question", etc). If you've proposed a tag wiki, wait until the tag wiki's approved before removing it.

Single-question system tags in need of attention

• the-multiverse-rpg (Are the rules for ignoring actions and having separate realities in contradiction?)
• rotworld (Is there a trick to learning the Pacesetter/Goblinoid Action Table?)
• mechanical-dream (Mechanical Dream rules gathered together)

Also, quite possibly anything in the untagged tag. If a system tag expires and it was the only tag on the question at the time, the question will wind up in untagged.