This game uses a connection between the two characters, but it is not a two player game. You have your main character that moves as a normal character would move in a platformer, but you also have the reflection that's moves are mirrored from yours. Your reflection is an ally at times, and an annoyance at others. Some puzzles will require using his assistance, and some will have him as a nuisance or a liability. The only thing that gives you the ability to move the players separately is the fact that they each have their own crate. Placing one crate does not place the other, so you can use this mechanic to your advantage. However, in the aspect of not spoiling too much I will stop talking about specific mechanics now.
The characters are moved with a simple "wasd" control scheme with A and D moving the two characters in mirrored directions. Then their are the crates, and these can be placed directly above the character by pressing either space or enter. Space will move the blue box above the main character, and enter will move the red box above the red character. A lot of the mechanics are implemented through an invisible tutorial, and can be learned by playing the game or are part of solving a puzzle. A puzzle may require you to learn a new mechanic, but the game will never assume you know something you do not. The goal of the invisible tutorial is to teach you of mechanics in the game in a simple way. If you ever do die during a level then the level will be restarted.
The game is going to be inside a zip folder, so if you unzip the folder you can double click the exe. Then you will be able to launch the game. Keep the screen resolution at 1024x768.