This is about  'Buffy-is-TV' though.

Original that became a post in May 2001:

Buffy v/s Polly - The god she fought before Glory

Before the initial Oct 2000 episode with the first
appearance of Glory, there was a 1999 Buffy  novel
where she fought a god with a somewhat similar name, Polly.

There appear to be some cross links between the book and
what later became the Glory arc in 2000-2001.
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(Expanded from an earlier post on WB Talk)

It was 'Power of Persuasion' by Elizabeth Massie.

I remember JW stating somewhere that the Glory character was created
initially by a writer (McKnight, deKnight?) from the blue. Yet there are a
number of curious common points that make one wonder whether that is
completely factual.

Massie's novel has Buffy fighting her first gods, whom she
eventually finds out are 2 of the Greek Muses (minor gods)
and their mother (also a minor god). The novel is set in high school.

The two daughter gods appear as Buffy's age.

They and their mother are super fast, immortal, invulnerable & immensely
strong.

One daughter is semi-insane with rage and kills male students for no reason,
by 'brain-draining' them --- literally, since Buffy discovers that their brains are
liquefied and flow out their ears.

The  gods only are made to 'die in this reality' and vanish in the
end to go back to Olympus, after Buffy alone recognizes their one
weakness and 'does what she has to do'.

The 2 daughter gods are suffocated under water and later
disappear with their god mother into the dimensional portal back
to Olympus, after another Buffy trick.

There's a student named "Ben" who is brain-drained by the more out
of control, semi-insane god Polly (short for the longer Greek name)
while she scratches on his neck with her fingers. (a la Glory's fingers
and her more sanitary energy brain drain).

Obviously JW/ his writers evolved a 3-D character for the Glory arc,
whereas Massie's 3 Muse gods were never completely personalized.

Might be why they also never told Clare Kramer, as she has said, much
at all about Glory's origin and past. Too much might have revealed a
trail back to Massie's uncredited novel.

Also that Glory might not be a true hell-god, but simply was transformed from
a minor Olympian god for the purposes of the Glory arc.

Still, it is a curiosity that there are these similarities.

It seems possible that, in spite of what Gregor the general said, that
gods can't actually be killed on this plane of existence. They still survive
to fight again another day.