Spy Ships are very important to target and destoy. Unlike Eddohru and kamikaze missiles, Spy Ships were manned. They don't have attack power but gives useful support. If a Spy Ship looks at you and manages to get away, you'll typically end up in a condition red alert scenario (not just if you taking too long while fighting enemies), with massive amounts of both Aihi (I-Type) and Puruah (P-Type) kamikaze missiles comes towards you severely. If you miss a Spy Ship the first time if you notice it, it'll typically pull a 180 and do another run or 2 past you. Don't let it get away during this time. The only other thing that can prevent a condition red alert scenario beside you shooting down the Spy Ship, is if the Spy Ship inadvertently collides with the Asteroid or a Cosmo Mine. In "Blast Off", Spy Ships appears in every first areas in the game. They come by going down and going up, and also by going down, going by sides, and going up. If you miss a Spy Ship, a Cosmo Mine will appear. They look like Galaga's Midori stingrays.