I have a rather interesting dispute happening on my wiki (not really mine but you get the point).
Basically the user came to the wiki and started editing articles as well as applying things that were (apperently) a standard on his own wiki. The quality was pretty poor so I cherry-picked the edits and kept things that fit the wiki standard and that were (in my opinion) better than the original.
He re-did the edits and stated in the descriptions that I'm abusing my power and that he will report me to Fandom if I continue doing it. He also wrote a message stating years of experience and rights elsewhere as a reason why I shouldn't touch his edits.
I explained what I thought was obvious and he again re-did some of his edits. This time just claiming they fit the manual of style. I explained my choices in more detail and undid these things again.
After that, he demanded me to make a new manual of style that would contain all reasons for reverting an edit and only go based on that.
As you can see, that's a ton of (creative) bad faith for a regular user but I don't know how much of it actually violates the policy and how much is just a disagreement.
Here's our discussion. Rest is in his contributions.