“Obra Dinn is a story puzzler that I can only recommend, but what piqued my curiosity as a software engineer is that it is a 3D game (using the Unity game engine) but rendered using only 2 colors with dithering.”
Two colours and a clever pixel pattern fool your eye into seeing gray. Printers and early Macs lived on this trick for decades. Most tutorials stop at one algorithm and a screenshot. This one shows the math and the failures, which is the part worth learning.