In the beginning, Arceus created the heavens and the earth.
And the earth was without form, and void; and darkness was upon the face of the deep. And the Hooves of Arceus moved upon the face of the waters.
And Arceus said,
“What?” Arceus turned around. Floating in the formless void was Mew, watching Arceus.
“Sup? Doing a little art project?” Mew asked.
“What are you doing here?” Arceus said. “I have yet to even create life, let alone a world for them to inhabit, let alone light to shine on them!”
Mew paddled its feet through the air as if swimming. “Yeah, but I’m the ancestor of all Pokemon, y’know? And you’re a Pokemon, so that means I’m your dad.”
“What? No, that is not possible!” Arceus yelled.
“You know it to be true, son!”
“Oh, fig this!” A Bronzor appeared, somehow. “That sucks! I’m going to write this part out of our Arceus religion!”
“OH YEAH WELL I’M MAKING MY OWN RELIGION” Mew screamed. “I’m calling it ‘Nya ^_^’ and it’ll have all the Holidays!”
And that’s how the two main religions of the Pokemon world were born.
-Odemon #151 Mew