Just watch. Turbo mode(press 'shift' and click the green flag) is recommended for faster generations. Try it multiple times, some generations don't quite represent what it can do! Biomes: forest, plains, desert, extreme hills, arctic, tundra, jungle
This project generates a random terrain. I used a sine wave that affects everything, even the hills. You can't tell that it is there by looking at it, giving a really nice effect. I can't even see it anymore. The hills are sort of generated from parabolas, but not quite. A hill can generate on top of another giving you a giant hill. the hills have different initial climbing velocities, giving you hills of various sizes. See it in action: https://scratch.mit.edu/projects/72469784/