Some concepts I liked:

* The game had simple but challenging gameplay. The controls were simple and easy to learn. Even though the gameplay only featured one button (the space bar), it was still fun, entertaining, exciting, and challenging. 

* I only used two guns in the game so far, but I am pretty sure the graphics and the audio of all the guns in the game are as great as the two guns I used. I liked how realistic and detailed the guns that I used looked like. When I pressed the space bar, the gun sound effects sounded so realistic and the sound effects made me feel powerful. The graphics and audio of the guns and the perfectly used particle effects from explosions and gun shots made the guns realistic. These guns' qualities made me immersed into the experience provided by the game.

Some concepts that I did not like:

* When first opening the game, the player is prompted a configuration window. The configuration window allows the player to change the screen resolution. When I was first playing the game, I changed the screen resolution to create a smaller window for the game rather than playing with the default screen resolution. This caused some of the objects in the game to not be visible on screen when I was playing, as the window was too small to show them. I would strongly recommend removing the configuration window in Unity because allowing the player to change screen resolution can crop some objects in the game out of the screen. Also, depending on your UI settings, it may even organize your UI differently when changing the screen resolution. I do not think this happened in the game though, so your UI settings might be adaptable to changes in screen resolution. However, I am not 100% sure. You will have to test your game to see if your UI is fully adaptable to changes in screen resolution.  In addition, you may also want to remove the configuration window because the input screen in the configuration window seems totally useless. From playing the game, it looks like you didn't use Input.GetAxis so allowing the player to modify which button maps to what control is useless. This is because changing these values does not change the controls in the game. The input screen may even confuse some players due to there being a lot of information. The input screen is not exactly explained too well, and it can be overwhelming and a burden to players. In case you are wondering, it is possible to remove the configuration window in your game.

* The directions of the game were not too clear at the beginning of the game. It took me some time to realize that I had to keep on going right to keep on progressing through the level until I eventually win in the level. I think the game would be better if it told the player clearly where to go rather than making the player find out by himself/herself.

Really fun game and incredibly creative difficulty system, make the weapon you choose decide how hard the game will be.

Probably the best game I've seen on this jam so far, very fun, very creative, very well put together.