Revenge of the Titans is great gem of a tower defense game. The upgrade path means you get some flexibility with the possibility that you’ll tech yourself into a corner and not be able to get out. That makes it all the more exciting once you finally figure out how to beat that next level with the handicap you gave yourself. For example, I had a hell of a time beating the last level on Saturn with that flying behemoth that came out! After experimenting and reading through things I realized I did indeed have something in my arsenal that was worth adding in to the mix: the Scanner. It increased the range of my turrets and made that level, and all levels past it, a breeze. To get to that point took me a while though, but I’m glad I went through it as it made the entire game more fulfilling and meaningful for me.