I haven't read any of the Christopher Priest Black Panther Stories so first of all I can't say if BP is a Batgod and second where Priest got his inspiration from. Grant Morrison's JLA run did start in 1996 however the Tower of Babel story line wasn't released until 2000 which is in general seen as of the biggest Batgod stories ever and where it is most evident. I'm not saying Batgod wasn't created earlier simply that Tower of Babel is one of the best know Batgod stories.
I'd peg it at Dark Knight Returns, actually. Previously he was very grounded, but DKR was the slow start of "He's got all the bases covered".
For some people Batgod is batman operating on anything besides street level.
Of course that's ridiculous but for some people Batman is strictly a street level character and his competence shoots up when he deals with things outside of gotham and his villains
Well for one the character is constantly evolving
Batman is now a versatile character and can be presented in so many different ways and they all fit the character and ring true
If Batman could only be envisioned as how he was created he wouldn't be popular today he'd simply be a pulp
That's why its stupid needlessly constraining the character and taking away anything that might be interesting when its been proven the character is much bigger than that.
Sure the character is evolving and never said that it wasn't however there is a difference between evolving and radically change what a character is. However all his connection is within Gotham. You claim that it rings true when he is in space yet many readers and creators don't feel that way. As for now it is now just a claim you have made with no argumentation behind it.
The problem is that you see a space adventure as being bigger when it can in fact just be different. It is not about hurting the character but tell the best story with the character and the is for Batman's purpose still in Gotham.
The Black Panther was a master planner since his inception. In his First appearance back in the 60's he defeated the Fantastic Four with planning. It was Roy Thomas who then turned him into a jungle acrobat without gadgets. A well written Black Panther should behave like a heroic non malevolent Dr. Doom in the body of Captain America.
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