Regular Brock or bloody Brock? Add a cold beverage to one of these clear 16-ounce pint drinking glasses derived from Adult Swim's The Venture Bros. and the blood appears. The image of macho secret agent Brock Samson, knife in hand, magically changes color! As the glass warms up again, the image changes back to regular Brock. The The Venture Bros. logo on the back of the glass also changes from white to red and back again. How cool is that?