The gameplay is rather leisurely and feels generic overall, despite the upgrade concept. The upgrades and the enemies bring variety though (especially the enemies)!
The visual style is solid and fits well with the mechanical theme, but offers few visual highlights.
The sound is functional, but some more sound would have been great!
The “Enemies are resources” theme is well implemented and runs nicely through the entire game concept!
A solid game that just needs a bit more polish :) Great job!