I'll say what I always say. No where in Pokémon does it say Arceus is the one and only God. He is only the creator of Shinnoh, possibly the world, but that is not proven.
"A number of monolatristic traditions separate a secondary creator, from primary transcendent being, identified as a primary creator."
^What Arceus is thought to be based on.^
So clearly we could be awaiting either the Primary Creator, or the Secondary Creator.
"Some stories state that the Qilin is a sacred pet (or familiar) of the deities."
^Another thought on what Arceus could have come from.^
This saying the Arceus would have been more of a pet than a major god. However, this Qilin ranks high, second only to the Dragon and Phoenix who are the highest in Chinese culture, so that would explain why he is made so powerful in the move.
- Spoiler:
Qilin and Arceus
"Ancient Philippines mythology varies among the many indigenous tribes of the Philippines. Some tribes during the pre-Spanish conquest era believed in a single Supreme Being who created the world and everything in it, while others chose to worship a multitude of tree and forest deities (diwatas)"
^Also sounds like Arceus.^
If this one is true, then we're in for well over 20 more god. So with over 20 games this gives pokemon a great way to keep making money for a good long time. Also proving my theory that Arceus is NOT the only god. Mearly the one who created the pokémon world. However, when they run up all the gods in this theory, they can pull up another religion with a good number of gods and say they created Deoxys's world, for those of you who do not know, Deoxys is an alien. This third theory fits Arceus's Story and name discrition the best, in my opinion, and it sets up pokémon for more games and money than anyone is thinking about. Based on those two reasons, look up the stories in the Ancient Philippines mythology to see where pokémon goes next.
Monkey