Ouch, sun fading is normally the best bet in most cases.. however for G4 ponies it can.. um kind of be iffy... I tried it with a G4 AJ bait base and I might of not had her out long enough but the ink didn't budge.. and depending on the pony and how long it will be left out.. there is a chance for the body to fade in color (apparently this can happen to pink Celestia)