This game is so damn clever. The key is the ability to rewire almost anything to its color coded components, and by doing so, you can absolutely run circles around the guards. In fact, you don't ever need to kill or sometimes even attack/take out guards; the vast majority of the game can be played strictly with pure stealth, and thanks to the game's constant autosaving, you can just keep experimenting til your plan sticks. With a wide variety of gadgets that you can purchase with in game bucks (which I never felt the need to do actually), there are so many different ways to approach the levels. There are optional objectives and ranks but they're more there to challenge yourself and if you want additional tidbits of lore from the world instead of mandatory completion marks. You can tell that it's fantastic level design because if you know what you're doing, you can finish the levels and the game super quickly (definitely under an hour). A great indie puzzler once you figure out how to not suck, and it's extremely satisfying.