Arceus as a character exists solely to restrict control over an otherwise highly abusable NPC to a responsible RPer
Behond--It is I, thy lord Arceus. (Also, Giratina is a dick.) The ultimate guardian of Ruula.
Arceus prefers not to directly involve itself with the affairs of others. Rather, it chose to and continues to rely on it's creations to govern themselves through a series of natural checks and balances. It now waits in the heavens for a pokemon trainer that is pure of heart to come and claim it as a worthy partner. Despite this, arceus is a very judgemental pokemon whose wrath can be provoked through extreme acts of evil. It is highly inadvisable to provoke arceus into action, as once it's wrath has been unleashed arceus will not stop until it has thoroughly brought it's offenders to brutal justice.
Powers
In the beginning there was nothing, and from that nothing formed a single egg from which Arceus was born.