This AVMA seemed like an interesting idea when I thought of it, but in hindsight probably was a mistake. :) And my commitment to exemplifying the AOTC with my answers has left me unable to communicate any nuance in my responses. You are all being too specific; the AOTC is a general (and very simple concept) that is a feature of many of the guesses you have collectively made.
[bl] Not a mythical creature. [B] Not fictional. [SM] The animals that could be involved are all chordates. [T] Not a hedgehog that thinks it's the King. Neither, for that matter, it is an elephant that thinks it's President Putin, nor a platypus that thinks it's Napoleon.
[T] That could be considered a political matter these days. [R] Yes, that's a reasonable description. The few who do not have it might kick up a storm about the AOTC being ableist, hence previous answer.
As I'm feeling generous, here are a few hints. 1. You'll probably need to come at this from both angles. That is, you need to identify what kind of thing the MINERAL thing is, and you will also need to figure out the ABSTRACT connection. 2. Most, probably all, of you won't actually know the specific wording of the AOTC. But an equivalent identifying phrase is acceptable (and, once you've figured that out, the AOTC would be a quick google away). 3. Despite (2), most, probably all, of you know the ABSTRACT connection and most—though probably not all— have in some sense encountered the MINERAL AOTC.
There are lots of geographical features associated with fiction, spanning the spectrum from Rockall to the Marianas trench. Does it span more than one country?