It's a fine first outing, but there's much room for improvement.
The story doesn't really introduce its concepts well. What is time splicing? What is involved in the process? Why do we need to kill this emperor? Questions like these should be answered early in the game to give the player a better idea of what is going on and why they are doing what they are doing. The "what is done is done/what is undone is undone" line should have appeared once or twice at least before being presented in the quiz; as it is now it comes out of nowhere and lacks any significance to the player.
I really don't like the trend I'm seeing with games not using battle backs in their battles. The fuzzy background just looks bad and makes the battle action hard to see. The battles themselves are very straightforward, and that's fine for a first game in a game jam, but I would like to see more strategic elements in the battles. Things like enemies that are weak to certain attacks and battles that go through various phases and require certain attack patterns to conquer are examples of how you can achieve this.
There are good points in the game, too. The maps are compact so it's hard to get lost, and while the directions provided in the dialog might be a bit too direct they do a good job of telling the player exactly what comes next. The puzzle in the room with the time agents & switches was clever. Battles, as straightforward as they are, don't last too long nor are too difficult to clear. Cutscenes don't last too long.
Congratulations on completing a project! I hope this is only the beginning for you and you continue to improve your game development skills.