Nice pixel art and animation. Relaxing music and appropriate soundeffects. Also interesting gameplay loop (initially). As prototype this thing is great. But after novity wore down (after 2 min), I felt bored. If I must guess, because upgrades did not feel meaningful (if I need 3 shots to take down enemy and after upgrade I still need 3 shots, what have changed) and there was not variety (for example, utility based such as time stop). Wall robots felt challenging opponents, but outside it there was little challenge. To sum up - give meaningful upgrades so after 2 or 3 I can feel overpowered and oneshot basic enemies, introduce bosses and elite enemies (mechanically, not just increasing HP and calling it a day). Add new abilities, which counter extra powerful opponents. P.S. Nice to see another Godot user.