Atari Invaders is a graphical hack of the game (it plays exactly the same as the original 2600 version), having changed game sprites, as the invaders, players' laser cannons, and the Command Alien Ship look different, as they were all changed into various Atari 2600 persona, as the player's laser base was changed to the player's ship from the 2600 game Asteroids, the bunkers is the Atari "fuji" symbol (plus players can shoot through the gaps in them), the row 1 invaders are robots from Berzerk, the row 2 invaders is Pac-Man, row 3 invaders is a player from Football, row 6 is a ghost from Pac-Man and the Command Alien Ship is a plane from Combat.
It is unknown who created the hack.
Moving Shields--Fuji symbols move back and forth
Zigzagging Laser Bombs--Invaders' shots zigzag back and forth towards the ground
Fast Laser Bombs--Invaders Bombs drop quickly
Invisible Invaders--Invaders are invisible unless one (or the plane) is shot, which they then briefly reappear
Large Player--flipping a difficulty switch on the 2600 console to the A position makes players' laser cannons larger