Haven't Groudon, Kyogre, Dialga and Palkia done this, really? They didn't nearly destroy their respective regions out of spite or hatred, they were just acting like any animal would that's been disturbed and roused from their sleep.
Yes, but at the same time, they don't REPRESENT destruction; they can most certainly cause it, but they aren't entities of destruction. Rather, they're entities of creation. What I mean is something that exists solely as a representation of natural destruction, an antithesis to Arceus who only exists as a way to balance Arceus's power, as Groudon does for Kyogre, Dialga does for Palkia, and Cresselia does for Darkrai... I'm not sure if there are more in that list that should be (I almost want to say 'as Lugia does for Ho-oh', but I don't think that's right). I just mean something that would represent the Omega to Arceus's Alpha, nothing more than a pokemon symbolic of the force of destruction that exists in nature to counteract Arceus's force of creation and act as a balance to the world of pokemon. There is, to my knowledge, not a single pokemon like that so far, and I know a lot about pokemon, so odds are that pokemon hasn't yet shown itself...