Nebulus on the Commodore 64 (also known as Tower Toppler in some regions) is a unique vertical platform game where you control Pogo, a small green creature tasked with demolishing a series of mysterious towers rising from the sea. Each level takes place on the outside of a cylindrical tower that appears to rotate smoothly as you move left or right, creating a striking faux-3D effect while you climb spiral stairways, ride lifts, and dodge or shoot strange geometric enemies. Getting hit doesn’t usually kill you outright; instead you’re knocked down to lower ledges—or into the water if there’s nothing beneath—while a strict time limit pushes you to memorize safe routes and tricky jumps. Reach the top and Pogo triggers the tower’s destruction before boarding a submarine for a brief bonus shooting stage between levels, making the game a blend of precision platforming, pattern learning, and technical showpiece for the C64’s graphics.