Just thought I'd let you know, even if a Pokemon matches all the information given on Serebii/Bulbapedia/wherever, it can still be hacked. Good hackers have access to all this information as well, and can input it in when creating a Pokemon to make it appear legitimate. Since the shiny Arceus was given to you by a complete stranger, it is almost assuredly a hack. I hope you didn't trade anything good for it :/
I saw your post on sqsr. If you're looking for breeding projects, check out post #8 on my thread. I have a ton of parents but not a lot of time to breed, so I'm always looking for people to help me out. Only payment I want is a perfect female with the nature and iv spread listed and any EMs the parent has, but you can always add more! Hope you find something of interest!
As chester's not available to pick up his Pokes from our trade, would you be available to take them?
I'm starting up a new trade thread soon and would like to get everyone's things tot hem, seeing as you and chester are a dual-thread.