Your pulse quickens. Beams, boxes, zig-zags and "L" shaped building blocks drop relentlessly down a narrow passage. You quickly spin, shift, and align the shapes then slide them in for a perfect fit. It's challenging and the pace is demanding. But satisfaction comes as you position each block neatly into place. Start at new heights for a tougher contest. Pick the music and set your pace from 20 progressive skill levels.