Delta is a horizontally scrolling shooter computer game originally released by Thalamus Ltd in 1987. It was programmed by Stavros Fasoulas and the music was written by Rob Hubbard.
The player character is a member of an elite police squadron called Delta Patrol, commanding a battle cruiser in the Delta Sector of space. The Delta Sector’s dangers include lost ships, alien bandits, and unknown forces of destruction, and the character’s assignment is to terminate the enemy forces that hide within them. Destroying an entire wave of attacking aliens earns credits that the player may use to buy weapons and ship modifications.
The player controls a spaceship and gains power-up points by destroying formations of enemies. Some enemy formations instead subtract power-up points for the player, so the player must take note of which formations to destroy. Periodically blocks containing the power-ups (higher speed, faster rate of fire) appear and the player can pick one of them up: The more points the player has collected, the more powerful are the power-ups that can be chosen. Unavailable power-ups are gray and kill the player if he flies into them, making them part of the obstacles in the game. The effects of the power-ups are lost over time and must therefore be regained. The player gets a choice between in-game music or in-game sound effects. There is also a high score table but no way to save it when the game is turned off.
The game was graphically very good and of course due to the fact that Rob Hubbard wrote the music it was also of a high quality, it was a very good shoot-em-up which just seemed to miss out on being a classic