old school 2D-scrolling shooter

 Ketm is a hicolor/hiresolution classical game that has similarities with
 Raptor, Tyrian and Galaga. You are a spacepilot controlling your secret
 prototype ship. At regular interval's you get attacked by the bad guys. You
 have a mission to clean this sector from them (i.e. Kill Everything That
 Moves). Be sure to pick up some weapon and ship upgrades on the way.