Use your Mouse to draw (pick your color from the left color palette) Press 'F' key to fill (under the mouse cursor) This is an adaption of my original flood fill to work using the pure color sensing blocks of scratch and no behind the scenes lists of pixels. This does mean that we are at the mercy of scratch's drawing accuracy, and as such you will note small errors at the edges of fills that only get worse the more you draw and fill over... Nothing we can do about that because I can't stop scratch adding those little error pixels at the edges of lines :/