So the sting skill has a code of spell_null looks like no one gets it etc... Maybe it is just not set right anymore?

It's set to the first immortal level so I think it's pointing to something that was still work in progress.

It seems like there might be a configuration issue with the sting skill code if it's pointing to an incomplete feature. Have you checked the settings for the skill level run 3? Maybe adjusting it could resolve the problem. It's intriguing how these details impact the functionality of the game mechanics.