Draw on one side, and the drawing will appear on the other side! Use the panel on the center-right to change the color of the brush. Click "GoG" to see what it would be like to platform on your art. Sorry, but it lags a lot. Another note, THIS DOES NOT WORK ON MOBILE. I will try to fix it in the future.
I was inspired by the Symmetry Studio. Thanks to @Semi99999 for the platforming script (I changed the script).