I didnt realize it was only a few hours, but it was fun the whole way through. I like games that make me feel smart figuring stuff out, haha. I did have to look up the 18th puzzle answer though. After i killed all the turrets i couldnt figure out how to get the cube, ended up that you needed to portal on a wall, hit a switch to make it at an angle, then jump down a portal to launch yourself like a cannon to the cube. The speeding out of a portal concept had been introduced, but thats the first they had you shoot yourself out of one at an angle. Never would have figured it out, ha.