First of, loved the idea of the Godot-robot head as an enemy narrator (fantastical adaptation and animation of it btw!). The tutorial being black and white and then the colourful gameplay had me by surprise! How did you manage that? Is there a filter for the tutorial?
Lot's of juice in this game: screen-shake, flashing enemies when hit (I assume an AnimationPlayer was used here?) the stationary-turret enemies had a nice touch with their guns telegraphing the shots.
I have a question: How did you pull the level design of? I mean, how did you craft it so that you die when you hit the wall-spikes? And what are the wall-spikes? StaticBody2D?
Well done!