Ar tonelico Series

ConsoleNameDeveloperLucca's Observations
PS2Ar tonelico II: Melody of MetafalicaGustBattle system different from the first, but the premise remains the same
PS2Ar tonelico: Melody of ElemiaGustTurn-based battles, platforming dungeons, some VN elements- protect the singers!
PS3Ar Tonelico Qoga: Knell of Ar CielGustSwitch in gameplay to real-time battles, songstresses become more powerful after removing clothes (sigh)