I am using this to teach my friends how to make things. Mouse and Arrow keys to move. Space to turn into a cat. If you want, you can make a game using this, just give credit.
Please note that anything you do in one ground sprite, you copy into the other. You can do this by clicking it, clicking "copy", going to the other ground sprite, and pressing "paste". There are also custom blocks inside that allow you to change certain things, making it so they stop if they are touching level. There is more text in the first remix.