The player has to quickly close the sections, timing it correctly to avoid collision with any of the foes or their projectiles. The enemies can be eliminated by connecting a section where they are standing, or by using one of the power-ups. The power-ups are stored inside boxes, that in some levels keep appearing and disappearing, and can be collected by removing a section with one of them inside. Most of the powers are temporary, giving lasers to destroy the smaller aliens, freezing the enemies for a few seconds, increasing the speed of the ship and helping in other ways. Each level is finished after removing at least 70% of the field, or if the large boss monster that shoots at random intervals is killed in some way. A port of the original game is also included, using the old assets but with a horizontal orientation.