To get it shiny, you must use the SID and OT of a second game. Then you trade the egg to the second game, where it will hatch shiny. It cannot ever hatch shiny on the game that receives the egg. There's a code to stop it, but the code doesn't work on a second game that receives the egg from the first. All shiny manaphy must have link trade in the description for this reason, but it will still be treated as a hack on GTS and for wifi battle recording, despite that it was gotten legitimately in the game.