The concept is unique and interesting and the art style is alo great! I also liked the music!
I think you should add more type of enemies which do different attacks or behave differently.
The bugs I encountered were ->
When you use the energy beam and use it again before the first one ends, it queues the beam and as soon as the first beam is over, it uses the second, you can queue up many beams this way, I think the all the beams should be cancelled if they are called during the first energy beam's animation
When you keep attacking an enemy during its dying animation, its animation gets stuck and the enemy just stays there until you reset the game
Overall an awesome entry to the jam! Great job!