PixPhys is a nice cheap sandbox game. However, my biggest complaint is the lack of explanations on any of the controls and what each piece does. It also seems to lack some quality of life key bindings that I think are crucial to a building game such as a key to bring up the move tool. The logic system, the gear shafts, the heating, etc. are well implemented, but without much of an explanation they might as well not exist because how are you supposed to work with them if they don't tell you that this input does that, the logic piece works like this, and shafts only connect if you place them with these pixels touching. I got the game on sale for a dollar and because of the price I can't say I wouldn't recommend it, but the game hasn't gotten an update in a while and the community speaks Russian. So, if you are fine with experimenting a whole lot and don't expect an update, this game is nice to mess around in. If the language barrier isn't an issue for you this game would maybe be easier to figure out than what I've experienced.

Great game, infinite possibilities.