Right off the bat, I really like the art. It's really nice! Same goes for the main character, it really drives home that sort of "astral projection" feel to it.
The parallax effect you guys used for the stars looks really good! Kind of adds to the whole vibe! I do feel, however, that the galaxy in the background ends up making the screen look too loaded with details. I feel like making the background galaxy at least a bit more dim would already help with that.
I also missed having upgrades for movement speed. In the 5 minute mark, the bigger variation of the 2nd enemy starts to spawn and they will always outpace your character, so it's either you have enough damage to kill them in one hit or it's basically game over.
I like the fact that you didn't go only for the four elements and that you made so many variations for the attacks depending on the duo combinations you make, even having different animations for each one! My favorite ones would usually involve Umbra since the damage was really good, and combined with Ignis, would make enemies bleed and explode, damaging nearby enemies. There was a lot of effort put into those variations and I felt like they're quite interesting! I do have to say though, I felt like the Air element was a bit on the weaker side, so I kinda avoided using it a lot.
Putting everything around the theme of the projection, including the descriptions of the different power ups, game over screen and etc really helped add to the ambiance of the game! I also didn't encounter any glitches during my play.
Honestly guys, really good job! I know what it's like to seem to never be able to finish a project and finally have a breakthrough, so I'm happy that you finished this! It IS something to be proud and happy about.
Good stuff for your first jam, and may this be the first of many finished projects!