A Spanish side-scrolling shoot'em up. The game is split in three parts, the second and third part are protected by an access code).
The game manual says (Alternative Software edition):
"Philipus Sunset, an interstellar megapilot from the TERRA 1 confederation, has "borrowed" the SPROCKET SYSTEM, stealing it from the dreadful DROWHAR empire. Rough times are looming: Philipus has to get back to his base with the SPROCKET SYSTEM in tip-top condition.
You enter the caves of OTNIREBAL, and when you come out an imperial gigaship traps you. Surprise! Your old pals from DROWHAR are waiting for you. Be tough and pray whatever you know: the battle will be final.
At last you enter the atmosphere of TERRA, where the confederation's headquarters are located. Watch out for the swarms of imperial ships. Destroy them all. The countdown has begun!"