Tower Stack has you clicking the mouse to build a tower as high as the eye can see. You'll watch the crane swing by with a block. The first one you'll want to click to drop on the base. The rest of the blocks have to be able to rest on that block or it's considered a lost block. Once you lose three blocks, the game is over! If you get one block perfectly on top of another, it turns gold and you get extra points. Otherwise just keep stacking and you can watch the stack meter in the lower left hand side to see just how well you're doing in this challenging game!