Did you use any of the additional themes?
Yes, we used retro as well.

give a brief discription of the game and how you incorporated the theme
The game’s core loop is one where you gain experience by fighting enemies, and then use that to get upgrades. When you upgrade yourself, you are mutating your stats - and the enemies mutate when you level up, becoming stronger and faster.

Do we have your permission to show and promote the game?