Aegis Wing

From Xbox Live Marketplace: "Aegis Wing is a side-scrolling space combat game reminiscent of classic Eighties arcade hits. It features alien-busting action, slick graphics, an orchestral soundtrack, and devastating power-ups. Also included is a unique cooperative mode of play in which up to three additional players can "attach" to the leader's ship and become independent, 360-degree gun turrets." This game is free in some regions. Playable on Xbox One as well.