Rhapsody:
You can see the roots of Disgaea in here. The bare bones of the combat, the art style and the sharply scripted, funny (and occasionally bleak) story. Unfortunately, this is all married to a rather tedious JRPG.

There's only really three dungeons, made up of about six screens each repeated ad nauseam with minor palette changes. The main challenge to the game is just navigating these mazes, which is not fun.

Combat is technically fine, but tediously easy and repetitive, especially once you run into some Metal Jellies, which allow you to very quickly power level (without even really trying) to the point that even the final boss is trivial. You could maybe complicate things for yourself if you ever decide to change up your party but there's really no incentive to do so - all the elemental stuff is fairly irrelevant - especially as every new character you get is at level 1.

Also, for a game that calls itself a musical, it doesn't really have many songs (which is of course a limitation of this being a PS1 game with limited storage, but still, it feels light on songs).