Hey ITR, thank you for trying my game and very much appreciated the effort for writing your feedback.
This is my main way to share the game with friends and to gather feedback, I am working on improving the stability, but right now it seems to be inevitable to have some bugs.
The idea behind "less xp" is that sometimes a quick level up with a lucky upgrade is all you need to save yourself from a tough situation. This curse is suppose to space out such saving level-ups. I agree that it doesn't make sense without more variety in terms of upgrades available.
the "destroy any tile you step on" was a bug, it was intended to be for a specific color. I have fixed that immediately.
The lack of indication for the UFO was bothering me as well, I added one more button. I think I will change it at some point.
This prototype doesn't feel mature enough to have proper options menu. That button is just a placeholder for now.
Some upgrades were meant to be stackable like the added hp or moving up with more than 1 square. I will make sure to have only stackable upgrades repeat in the future.
My biggest problem is with the enemies standing still. It is a problem that has been plaguing me for a long time and I feel like I need to rewrite many things to get rid of that problem.
Thank you again for your comment. It is very motivating to see people care about your game.