Great idea! Taking the power of my enemy seems like the main hook of the game, and I'd consider it the strength of the game as well! I can imagine targeting certain enemy types just so I can use their attack against another type that's weak to it. I think you could address an area of friction I had, which is how loud the (epic) music was, by adding a volume slider. Good work so far :)
Also, one of you was in the audio workshop today. You could bring your sounds into Audacity like Mr. Horowitz showed you to produce them a little more. It would be easy to balance the levels a little more before adding to the game. Sure you can adjust the audio in Godot, but getting them more balanced from the start will make less tweaks needed later. Plus it's jarring once the loudness kicks in, not in a good way.
I love the effects you have gotten in the game so far, especially the lightning, I'm a sucker for lightning effects. Give us a preview of the art that will be in your game. To improve this Itch page add images of your player, enemies, pickups, world and take advantage of the banner option. Whet our appetite until you can add more art in the game.