I was thinking, if Mew created life in the Pokemon World, the other "PokeGods" can fit in. Areseus (uh, SP) could've created the sky, atmosphere and objects like that - Dialga created and controls time. Palkia created space. Groudon and Kyogre created land and water respectively, while the Elemental Birds and the GSC Dogs/Cats/WhateverMutantTheyAre control the elements Water, Fire and Thunder.
There are some things that I think the other (not too important storywise) Legendary Pokemon control/created. Giradina created Hatred/Rebellion as it is called the Rebellion Pokemon. Darkrai made and controls death, Sheimi created Happiness/Gratitude, again, since it's the Gratitude Pokemon. Celebi is a confusing Pokemon to classify since Dialga created space and controls it. Celebi's moveset consists of moves like Heal Bell, Safeguard, Recover, Protect and some Grass/Psychic offensive moves. This makes me believe that Celebi controls growth, restoration and healing. Jirachi possible maintains stuff like wishing and luck. My opinion on Deoxys is that it really isn't a legenday, but is a space mutant (for lack of better words). The Regi trio and Regigigas also aren't legendaries, but they are huge, powerful Golems.
If you have any problems/comments/anything, please don't be afraid to reply.
There are some things that I think the other (not too important storywise) Legendary Pokemon control/created. Giradina created Hatred/Rebellion as it is called the Rebellion Pokemon. Darkrai made and controls death, Sheimi created Happiness/Gratitude, again, since it's the Gratitude Pokemon. Celebi is a confusing Pokemon to classify since Dialga created space and controls it. Celebi's moveset consists of moves like Heal Bell, Safeguard, Recover, Protect and some Grass/Psychic offensive moves. This makes me believe that Celebi controls growth, restoration and healing. Jirachi possible maintains stuff like wishing and luck. My opinion on Deoxys is that it really isn't a legenday, but is a space mutant (for lack of better words). The Regi trio and Regigigas also aren't legendaries, but they are huge, powerful Golems.
If you have any problems/comments/anything, please don't be afraid to reply.