Defender

Bat Attack is a Galaxian clone, in which you control a ship that must constantly move left and right firing at a series of bats that swoop down with your laser, while avoiding their bullets. The bats swoop down until they fly off the bottom of the screen and re-appear in the group. One of your lives gets lost when one of these bats come in contact with the ship. Once you have wiped the bats out, you must then avoid the spinning discs that come down the screen. When you have avoided enough discs, the next level begins.

Space Armada is a clone of the game Space Invaders. Rows of bomb dropping aliens are invading your home planet, and you need to protect it! You control a laser gun at the bottom of the screen; your goal is to earn as many points as possible by destroying the waves of attacking aliens at the top of the screen. The aliens march steadily downward, and if they reach the ground or you run out of laser guns, the game is over. When all aliens in a wave are destroyed, you move on to the next, more challenging round. From time to time, a flying saucer will pass by at the top of the screen which can be shot for bonus points.

Space Attack is an arcade shooting game, released by Sega for VIC Dual hardware in 1979. In the US it is thought to have been renamed Super Space Attack - whether there are in fact two separate games is currently unknown, but the two are extremely similar and "Super" is often dropped in internal Super Space Attack documents. It's a Space Invaders clone and is almost identical to Taito's classic. It is completely identical to another VIC Dual Space Invaders clone, Alpha Fighter, sharing full color graphics and a "bonus" round (in which the saucer briefly descends from the top of the screen after clearing the rest of usual set of invaders). Space Attack has a different set of graphics to Alpha Fighter, however. Similar to versions of Space Invaders, the upright cabinets for Space Attack use a mirror to project the image onto a textured surface (in this case, a starfield), giving the illusion that there is a background while playing.

Avenger is a Space Invaders variant. The player has to defend Earth from endless rows of attacking aliens. Flying saucers can be shot for extra points.

A clone of Space Invaders and Galaxian. Released in Sega Mega Drive Flashback.

Space Invaders clone released by Ryuto Electric Co. in 1980.

The attackers from outer space are back. This time, however, they are stronger and tactically better prepared to bring the world one step closer to its doom. Practically, this means blasting everything movable into little pieces and collecting bonus items. In higher levels, the enemies become faster and more aggressive. At the same time, their bombing frequency also increases. There are also several different enemies that break away from the formations and attack the player.

Pineapple 2000 is a remixed and revamped version of Space Invaders that pits a gingerbread man warrior against an army of invading Fruitoids.

Space Invaders Clone by Roklan

Space Guerrilla is a fixed-screen shooter in the vein of Space Invaders but with some interesting twists. The player controls their tank at the bottom of the screen and must prevent an alien invasion. Instead of the typical four bunkers, there are three pieces of scenery with buildings. The attract screen starts with a little animation of aliens landing on one of them and peeing. Another difference with the typical Space Invaders clone is that while the ships fly in a block formation, they don't go back and forth between the screen boundaries. Instead they fly past and go out of view again, before flying back. Some ships also dive down towards the bottom of the screen like in Galaxian. When the player loses all their lives the game is lost.