Why you may ask? Well just look at this then see what is wrong... I made a promise to mesprit that if I caught it in a dive ball (As a joke) I would give it this item and I said "Your just jealous you don't have a mega. Okay stay in the ball and I will give you a mega stone." *Click* "Oh shoot" @magicnerd808 knows about this when it was deoxys.
Pshhh. My Shiny arceus was carrying a master ball... Sadly master balls don't go through poke bank ;-;