When you press the space bar on your keyboard, the character will turn different colors and music will play. This will not stop on it's own so to stop the music and color changing, you need to press the red button next to the green flag on the project screen. Or you can click on the green flag. When you click on the green flag the character says hello and makes an excited face like it is happy to see you. ( stare at it for a while and the background looks like it's moving )
The credit for the character, color changes, and the drum beats go to scratch.