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UFO is the Sample Program 3 of the original version of Family BASIC before V3, available as a type-in exercise from the manual[1]. It is also included within Side A04 of the sample Famicom Data Recorder Tape (audio read as data/code) contained within the package.
Gameplay
Try to earn 10 points by shooting at a moving enemy (uses the Fighter Fly asset), while the player also tries to avoid the enemy firing at their own ship.[2]
References
