That mysterious Blue Spell

On my play through of Final Fantasy V Advance I encountered something mysterious, mainly a spell only marked as ??? when confronted against a Bone Dragon when rescuing a Moogle on Galuf's World. After defeating it my Blue Mage learned it and it costs 3 MP to use, dealing only minimal or no damage at all to any foe, plus the fact that it won't work if you invoke it against the same enemy within a battle. I am not sure if this is a glitch or was put there intentionally. So far my search about this mysterious spell has come up negative. Quite frankly after having it around I was wary that if I used it it would do something to my save file or glitch the game. Good thing it hasn't.