Alien Invasion is notable for being the last title ever released officially on the Channel F. As you can imagine, this is indeed a Space Invaders clone.
Easter Egg#
To activate this Easter Egg, the game must be started on Game 5. When the game starts, Player 1 (blue) must be killed by an alien bullet without firing any bullets in return. Then, Player 2 (green) must shoot only the lowest enemy in each column. After this, both players must lose the rest of their ships without Player 1 firing their weapon. After the game ends, it must be started again on Game 5. If all of this is done correctly, programmer Brad Reid-Selth's last name will appear at the top of the screen each time the players' ships appear, before the aliens start to move:
In addition, the sprite for the special bonus UFO will be replaced with a duck:
Both effects will last as long as Player 1 does not fire a shot.
Source Code#
Two small tidbits were left behind in the game.
The first can be found at offset 0xC77...
************* BEGINNING
****************SCREENST
**************** OF
****************,PUTLIST
**************** PROGRAM
****************,PUTLIST
* DC H'0080'173'MUSICEUTMISL,PUTDOT,PUTLIST
* DC H'4040'D80'MUSICEUTMISL,PUTDOT,PUTLIST
...and the second one at 0xF35:
TDOT,PUTLIST
***** DC H'0140'953'MUSICEUTMISL,PUTDOT,PUTLIST
* DC H'FF01'500'MUSICEUTMISL,PUTDOT,PUTLIST
