Click the green flag to generate tiles using a random tile design and color offset. Look inside to see how it works. And check out the original project, which has simpler code. Here is how you make tiles: https://scratch.mit.edu/projects/572028611/
When I saw @crkcity's wondeful project I just had to remix it with my own tile designs. While working on it I made some other changes and additions as well, such as sound and randomized colors. The resulting code is not as simple as in the original project though, so if you have problems understanding the code, check out the original first. Check out @crkcitiy's other tile-related projects - they are very interesting! Especially if you like M.C. Escher.