Space Invaders Duel looks and plays pretty close to the original Space Invaders, although it has a few new twists, such as having the player choose between playing in the "classic" mode or as the Invaders, along with a two player simultaneous mode, one player controlling the humans, the other controlling the Invaders.
Even with the basics of the original game being intact, there are several differences with the basic Space Invaders Duel game.
The Invaders move a bit quicker from the very beginning. The bunkers are also slightly differently shaped. The saucer makes no sound, and not only fires back at the player, but if its shot hits a bunker, it will cause an explosion, sending pieces of shrapnel everywhere. However, the debris is harmless to the player, as only a direct hit will destroy their laser base. Every time the Invaders fire it also produces a sound effect, sounding close to an Invader being shot from the original game. The saucer also makes an exploding sound this time around when hit.
The player can also play as the Invaders, clicking on which Invader they want to drop a bomb towards the laser base. Two players can also play at once, one being on the humans side (i. e. the laser base) and one controlling the Invaders. If the Invaders are able to wipe out all of the human's laser bases, the game ends, saying "INVADERS WON!" If the human wipes out all Invaders after one screen, the game ends, saying "HUMANS WON!"
- Bottom two invader rows–10 points each
- Middle two invader rows–20 points
- Top invader–40 points
- Flying saucer–random amount
- Move laser base–arrow keys (left/right)
- Pause game–P key
- Mute sound–0 key
- Turn sound up– - key
- Turn sound down–+ key
- Have Invader fire–left mouse button on Invader