According to the manual, the Atari 2600 version of Defender is almost identical to the arcade version. But since most of us don't have access to the arcade version, we'll concentrate on the features and limitations of the Atari 2600 cartridge. The differences are very minor and should not detract from your game enjoyment. We're using the most capable emulator for the 2600, the Stella emulator. As this is a game guide, not a walkthrough, it focuses on explaining the game, the different game variations, scoring and a few secrets that most of us never knew. After all you would have had to actually read the manual that came with the game. PFFFT. Whoever did that?
For complete instructions and a walkthrough
watch the video below