Space Invaders (C64)

This game is a C64 conversion of Space Invaders, the famous arcade game created by Tomohiro Nishikado in 1978.

The game runs perfectly on both PAL and NTSC models of the Commodore 64.

If you are using an emulator on a 60 Hz monitor, it is recommended to select an NTSC model for smoother gameplay.

Gameplay

Space Invaders is a fixed shooter in which the player controls a laser cannon by moving it horizontally across the bottom of the screen and firing at descending aliens. The aim is to defeat five rows of eleven aliens that move horizontally back and forth across the screen as they advance toward the bottom of the screen. The player's laser cannon is partially protected by several stationary defense bunkers that are gradually destroyed from the top and bottom by blasts from either the aliens or the cannon.

The player defeats an alien and earns points by shooting it with the laser cannon. As more aliens are defeated, the aliens' movement and the game's music both speed up. Defeating all the aliens on-screen brings another wave that is more difficult, a loop which can continue endlessly.

A special "mystery ship" will occasionally move across the top of the screen and awards bonus points if destroyed.

The aliens attempt to destroy the player's cannon by shooting it as they approach the bottom of the screen. If they reach the bottom, the alien invasion is declared successful and the stage starts over with the loss of a life (Novice and Medium difficulties) or the game ends tragically (Arcade difficulty); otherwise, it ends generally if the player's last cannon is destroyed by the enemy's projectiles.

The player earns extra lives based on the scores shown in the following table:

Difficulty level	First life at	Subsequent lives every
Novice	1000	2000
Medium	1500	3000
Arcade	1500	-

A maximum of 9 lives can be accumulated.

Options

There are 3 difficulty levels to choose from: Novice, Medium, Arcade.

You can toggle the autofire on/off.

There are 3 color sets to choose from.

There are 6 fire sound effects to choose from.

Controls

Joystick lever	Move laser cannon left/right
Fire button	Fire
F7	Pause
F1	Stop game and return to title screen
F1	Reset ranking (while the top scores are displayed)

Joystick in port 2.

History

Version 1.0

• First release.

Version 1.1

• After the last alien was hit and before moving on to the next stage, the remaining enemy projectiles passed through the defense bunkers and the player's cannon.
• Added "Score Advance Table" animation to title screen.