Galaxy Invasion Plus
Galaxy Invasion Plus was an update to Galaxy Invasion with a few new features added. An important difference from the older game is the voices. The speech include “Galaxy Invasion” (at the title screen), “Prepare to die, human!” (as the game starts), and “Game over, Player 1” (when the game ends). Other phrases that are used include: “You’re dead!”, “Flagship alert!”, and “Extra ship!” If you achieve a high score, the game says, “Great Score, Player 1”. But if you beat the top score, it says “Super Score, Player 1”. The speech is very clear and one of the best examples of voice in a TRS‑80 game.
One new feature is the ability to pause the game. The screen flashes between white and black while it is paused. Another new feature is the option to turn off all sound.
The most noticeable change in Galaxy Invasion Plus occurs after 50,000 points; the screen flips vertically. Although otherwise the play remains the same, this is surprisingly distracting and adds to the difficulty of the game. After the first flip, the screen changes between normal and inverted every 10,000 points. The game is noticably slower while the screen is flipped.