I'm sure you don't need me to sell you on this game, but it's an actual masterpiece. Everything about it comes together so fluidly. It's exactly the right length, just challenging enough, and has a story you'll actually want to pay attention to. Plus, it's just funny. Almost every joke lands. I honestly prefer this to Portal 2, so I highly suggest you start on this one. Plus, being an FPS without an enemies, this is the PERFECT game to learn how to shoot on M+KB. Or if you have a friend who's learning how to move in a 3D space for the first time in a game, this is the one to give them. They can take their time, figure out what does what, and learn to shoot all without the threat of enemies or combat but still with enough challenge they'll feel good about conquering obstacles. This game is like $2 on Steam right now. What are you waiting for? Go buy it!