master codes: must enter! EA995F78 808AC7FC 15354346 20E97650 572905DE EC7804A2 - Quick Lvl Up D0D63EAA FD4C724B - Infinite HP 6D9304A8 EA65A137 - Max HP 2E36CA0F FD9DBA83 - Infinite MP B7A2F308...
http://www.gamefaqs.com/portable/gbadvance/code/930370.html try above s Arbab Ali
The Lunar Ruins possibly wasn't ported to the DS remake, hence the title, "GBA- Exclusive."
http://us.codejunkies.com/search/codes/cheat_codes.aspx?selp=3&game=Final-Fantasy-IV-Advance&gameID=3147817&page=0
yes go to www.gameshark.com click on codes then handheld then f then final fantasy IV or final fantasy IV - EUR (depending on your version)