GAME OVERVIEW

Space Invasion follows a simple yet classic formula: destroy the waves of aliens before they descend to the surface and wipe out your ship. You are armed with a limitless supply of bullets, and have three ‘shields’ which you can use as protection from the enemy onslaught.

The game is divided into five stages, each comprising ten waves. Each stage is set against a different backdrop (representing different areas of the solar system), and features a wide array of enemy types.

GAMEPLAY

The gameplay in Space Invasion is simple: your ship moves left/right along the bottom of the screen, while the enemies above move left/right, descending slightly whenever an enemy reaches the edge of the screen. The aim is to destroy all of the enemies before they reach the bottom of the screen (or your lives run out).

You start the game with three lives (which can be changed in the OPTIONS menu), and three credits (which allow you to continue from the current wave should you lose all of your lives). An extra life is awarded every 10,000 points. After losing a life, your new ship is temporarily invincible for a few seconds.

ENEMIES

MOVEMENT: The more enemies are shot, the faster the survivors move. When only eight enemies remain, their speed increases dramatically. The last enemy on each screen moves very fast, but slightly more slowly from right to left than from left to right.

START POSITION: The second wave of enemies in each stage starts one row lower than the first, and so on throughout the subsequent waves. The enemies return to their original height at the beginning of the sixth wave.

FIREPOWER: Enemies randomly fire bullets, lasers, and bombs; bullets and lasers can both be shot out of the sky (bullets require one shot, lasers require two), but shooting bombs has no effect. Bombs and lasers, due to their power, are only ever dropped by certain enemies, which will usually only be present in the top two rows. However, no enemy can fire when it is in the second row from the bottom. The frequency of the enemies’ firepower - as well as their speed - is affected by the SKILL setting on the OPTIONS screen.

FLYING SAUCERS: Flying Saucers appear at random every 25 seconds or so, travelling across the top of the screen from right to left (and vice-versa). However, a Flying Saucer will not appear if there are eight (or fewer) on-screen enemies remaining. The Flying Saucer is worth 50, 100, 150, 200, or 300 points, chosen at random, but this can be doubled by using Advanced Strategies.

ADVANCED STRATEGIES

Space Invasion utilises a cunning bonus system which allows you to rack up increasingly higher scores, and gives the gameplay a significant twist:

• Begin counting your shots fired as soon as each wave begins. Fire 22 shots and then wait for the Flying Saucer to cross the screen. Use shot number 23 to hit the Flying Saucer and you will receive double the points.

• After hitting the Flying Saucer, start counting shots again. This time, count to 14 and use the 15th shot to hit the Flying Saucer. Once again you will receive double the points. Repeat counting using the 14 shot method until the wave is cleared.

• When the next wave starts, repeat the procedure using 22 shots, 14 shots, 14 shots, etc. Make sure you count every shot, regardless of what it hits. If your ship is destroyed, continue counting where you left off.

 

CONTROLS

• MENUS: The Dpad and A and B buttons are used primarily for selecting/adjusting menu items, while START is used to exit sub-menus and/or start the game.

• IN-GAME: The Dpad is used exclusively for moving your ship, with the A and B Buttons used for firing bullets. The START Button brings up the PAUSE MENU.

OPTIONS

The following settings can be changed in the OPTIONS menu:

• LIVES: Choose between 1, 3, and 5 lives.

• SKILL: Choose between EASY, MEDIUM, and HARD.

• SOUND: Choose between MUSIC, SFX, BOTH, or OFF.

• STYLE: Choose MODERN or CLASSIC enemies (MODERN enemies animate continuously and move pixel by pixel, CLASSIC enemies animate as they move in large steps).

PAUSE MENU

Pressing the START button during the game will pause the action. From here, you can push UP or DOWN on the Dpad to choose CONTINUE or QUIT. Press the A button to choose an option, or press START (or the B BUTTON) to un-pause the game.

CONTINUE

After the Game Over message - and providing there are credits remaining - you are given the option to continue from the last wave you reached. Selecting YES allows you to start from the wave on which you were killed, along with a full quota of lives (according to the number of lives chosen on the OPTIONS menu). You start every game with three credits.

HIGH SCORE ENTRY

Should you lose all your lives/credits, and providing your score is good enough to earn a ranking in the Hall Of Fame, you’ll be given the opportunity to enter your name (up to five characters long). Use UP/DOWN on the Dpad to select an alphanumeric character, and the A and B Buttons to confirm your choice. Characters can be deleted by selecting the arrow symbol, and entry concludes when you enter the fifth character or select the ‘ED’ symbol.

CREDITS & ACKNOWLEDGEMENTS

Design, Code, and SFX: JON WELLS

Background Art: MICHAEL SMITH

Enemy Art: PAUL 'DOKK' DOCHERTY

'Delta' Soundtrack: ROB HUBBARD

Playtesting: JASON MACKENZIE

Production & Additional Art: ANDY ROBERTS

Original Cover Art: STEVE & CLIFFORD ABRAHART

Cover Art Remastering: GARY ARNOTT

Special Thanks: CHRIS ABBOTT (C64audio.com)

A PIXEL CHICKEN production for Thalamus Digital.

RUNNING THE GAME

The Space Invasion ROM is designed for use with a Game Boy emulator such as mGBA (compatible with Windows, Mac, Linux, and Ubuntu) or a flash cartridge such as the EverDrive.

© 2023 Pixel Chicken Ltd. Game Boy™ Color is a trademark of Nintendo Inc. This product is not sponsored, endorsed, or approved by Nintendo.