|Mode||Single player only|
The basic gameplay of the online game Galaxy Invaders is like Space Invaders, although with many differences and enhancements.
Like with Space Invaders, the player controls a fighter ship at the bottom of the screen while invaders move in formation overhead, dropping bombs at the player all the while. Once the invader formation reaches a screen edge, they will drop a notch closer to the player. If the player gets hit by an invader bomb, they will lose that fighter, and if there are no more ships left the game will end. A bonus U. F. O. also appears several times during a round over the invader formation, which is worth more than most invaders (see Scoring section).There are many differences with Space Invaders, however. There are no bunkers for the player to take cover behind. Their fighter ship can fire several shots at once (most Invaders games only allow one shot at a time). The player cannot get invaded (i.e. when an invader reaches the bottom of the screen, ending the game then) once the bottom few horizontal rows of invaders have been cleared out, as the invaders will not move any further down than right above the player’s fighter ship.
Once the bonus U. F. O. appears overhead, if the player does not dispose of it quickly, it will start dropping down invaders. Shooting the U. F. O. will release a bonus power-up, however, and occasionally an invader will drop a power-up as well. The invader formation and number of invaders also changes per level.
The further the player gets into a game, the difficulty level will rise, as the invaders start firing quicker. Certain invaders start taking several hits before being destroyed. Yellow invaders also start appearing after several levels, which will leave the formation and quickly make a beeline for the player’s fighter ship (like with Galaxian); if these invaders do not collide with the fighter ship or the player does not shoot them, then they will reappear back in the formation. A mother ship will also appear far into the game, taking several hits before being destroyed, and if the player makes it to the second mother ship and destroys it, the game ends (see Trivia).
A power-up must be touched by the player’s fighter ship in order for it to activate (in most cases; see Controls).
- Fireball–fires a fireball that passes through several invaders (one shot duration only)
- Missiles–equips fighter ship with missiles; six per power-up
- Money–worth 500 points
- Rain of missiles–automatically fires several missiles at once
- Shield–protects fighter ship; disappears after collision with invader or invader fire and once a level is completed
- Time–slows down invaders for several seconds (except for diving invaders and bonus U. F. O.s)
- Shooting an invader–10 points
- Shooting an invader from U. F. O.–5 points
- Multiple hit invader–10 points x number of hits to destroy
- Collecting a power-up–10 points
- Money power-up–500 points
- Bonus U. F. O.–20 points
- Mother ship–various points per hit
- Extra fighter ship awarded every 4,000 points
- Start wave–left mouse button
- Pause game–P key
- Move fighter ship–mouse (left/right only) or left/right arrow keys
- Fire–left mouse button, spacebar
- Fire missiles–control key (when applicable)
- A player’s entire missile stockpile will disappear once their fighter ship is hit, with no matter how many they may have in reserve.
- The bonus U. F. O. always appears from the right side of the screen and travels left, never appearing from the left side and traveling right. It also has to be destroyed or escape if it’s the last one onscreen at the end of a level in order for the player to advance to the next wave.
- The final invader left at the end of a round does not move as fast as the final alien does on most Space Invaders games.
- Once the second mother ship is destroyed, the game ends. A congratulatory screen states that if the player wanted to secure a downloaded version of the game, they could do so from justfreegames.com, although as of late 2014, the game did not appear on that web site. It is assumed the downloadable version's gameplay continues past the second mother ship.
- On the above ending screen, the game is misspelled as "Galaxy Invaiders".