What are 'arcane shadows' for you?

[Pennarin]

The only time we read about it is a comatose Korgunard sending visions, the titular ‘arcane shadows’, to PCs/NPCs in the adventure.

But what is it? What’s its extent?

[Plortius_Maximus (Connor)]

Seems to me like a sort of psychic or spiritual imprint of an arcane magic user on Athas, sort of like a warp presence in 40k or perhaps analogous to the shifting tides of warp (or in this case arcane) energies

[nijineko (nijineko prismaticpsion)]

@Pennarin

The only time we read about it is a comatose Korgunard sending visions, the titular ‘arcane shadows’, to PCs/NPCs in the adventure.

But what is it? What’s its extent?

Context? Quote please?