Weighing Nine Cinderblocks file

Using a scale, find the different cinder block among nine of them, and use it to get your hand on a revolver. There is nothing more to that. Or is it? This map was made as an entry for Maplabs and RTSL's DeceptionVille competition, where entrants were challenged to make a map wherein something isn’t what it first seems. Watch out for major spoilers on the screenshots.