This one's really cool. I love the art (and color choice), and doing isometric with GB Studio is very impressive. The environments seem full despite GB(C?) limitations. I also love the presentation of the battles. The health bars, along with the camera panning down into the arena, and the arena itself resembling the overworld placement/environment is super cool. I love that different battles have the characters in different positions. The final boss was super cool, I was surprised to see something so intricate for a game jam game.
Unfortunately, I didn't gel with the gameplay as much. I'd say it's the only weak point in this project. The overworld isometric controls are a struggle. In particular, if you hold a diagonal direction, your character stops entirely, which causes some grief in combination with the isometric view. I've seen how GB Studio handles input, so I'm sure they're not making it easy. Sometimes the collision pokes out in unexpected ways as well, like around doors. I noticed the game chugs a bit on my SP compared to the web player, which is unfortunate since the game looks so good on it.
The battles were alright, but a bit simple. The gameplay does feel a little bit railroaded; I think I would've preferred more monsters appearing at a time, so that I could whittle them down while searching for weaknesses.
None of that ultimately takes away from what works so well for this. This seems like it was a really tough project to make, and the final result is super impressive. I think it's splendid.