Cool intro.
Initally did not know what the difference was between fuel and energy.
Some tip on UI design
- Maybe better to show the 'not enough energy' when you hover one of the upgrade buttons and show the actual upgrade or icon in the text or some short word for the upgrade so it is more clear for the player.
Sometimes it seems that gems spawn within the view of the player.
I played this game for quite a long time, it could be cool to add a lives upgrade so you can get hit multiple times, the birds got kinda annoying after some plays.
I found the other planet 🏆