I always imagined it as Arceus realizing all the Effort you put into reaching The Hall of Origin/Area of Capture and deciding on a whim to accompany you for a while, after all... What's a century to a Deity?
Trade Partners: I Do not knowingly accept Hacked pokemon, Nor will I Knowingly trade them out. 3052-9840-7953 - Pokemon Black FC
then how can he or she be enslaved by a 10 year old???
Quite simply - through an avatar (not of the Aang, Korra or Na'vi type, though). Didn't you ever wonder how there can be so many supposedly rare or unique legendary Pokémon in people's possession? That's because they've never actually shown up personally! When Arceus created the 'kings' (that's what I call the legendary Pokés with power over an elementary part of the world), he only created self-conscious spirits with the power to control specific aspects of the logical world he created (Pokémon Logic, still). These spirits keep creating self-conscious avatars with powers to reperesent their responsibility or reason in the universe. These avatars are used to observe the world and take influence on a logical base - in a way that humans can observe and understand the changes. This prevents mankind from relying on the kings themselves as gods, since the avatars make it seem like they don't fit the idea of a god or divine being (being omnipotent, undefinable, and inapproachable). It also protects them from technological advances which could threaten them, as mankind has no apparent reason to search for the king's spirits in the first place. Now, if a trainer manages to catch it, he/she passed the test the original king burdened him/her with. All a concept of developing new bonds between humans and Pokémon. And later on, the king's avatar will be remade to fill the gap. Arceus is a genius!
"Evil beware - we have waffles..." - Raven, Teen Titans I TRANSLATE!!! http://www.gamefaqs.com/boards/959197-tales-of-graces/64405766