This one time I ran into a shiny Houndour... and I didn't have any poke balls. I was very depressed for the next week or so.
~ Inspector Hound
It's impossible because Celebi is only available through distribution events and therefore is subject to a shiny check.
Upon doing a little more searching, I've found it's only possible to have a legitimate shiny Celebi in a Gen 2 game. You don't play Gen 2 on a DSi, so that can't be it.
Bulbless the Bulbasaur, because I was too lazy for the bulb.
This one time I ran into a shiny Houndour... and I didn't have any poke balls. I was very depressed for the next week or so.
~ Inspector Hound
You do not stand a ghost of a chance.
http://superskarmory.net/forum/showt...ppers-Nuzlocke!
That thread.