A while back I did this for various Half Life 2 mods. I thought some people might be interested in this. Note: Score is based on how often I cheated and or looked up the solution. I tell you truthfully that I’m not a very good video game player so your experience might be different.
Rexaura: 8
Gamma Energy: 10
Portal Pro: 8
Portal Flash Map Pack: 10 (Not the Flash based game)
Considering the title says “review”, maybe you could say something about what these mod are about?. Are they extra levels?, do they change gameplay in any way?
They’re all pretty much puzzle type FPS like Portal. Each mod is pretty much a complete game. Some even have bonus chambers. Most mods usually bring something new to the gameplay, but it’s usually not anything you can 't figure out. None of these mods have anything startling.
They all had bonus chambers. In Rexaura and Portal Pro you had to find the cakes to unlock the chambers. In Gamma Energy you had to complete a certain percentage of the game to unlock the chambers.