Gravity Force

The Earth is under attack – and you're the only defence it has.

Gravity Force is a fast, old-school arcade shooter. Asteroids rain down from deep space towards the planet below. Aim your crosshair, click to fire your twin laser beams, and blow them out of the sky before they smash into the Earth's shield.

How to play

- Move the mouse to aim, click to fire.

- Each wave sends 50 threats at the planet. Shoot them or they hit your shield.

- Destroyed asteroids tumble down at top speed – and still count when they land harmlessly.

- Watch the Earth Shield meter. When it runs low the warning sounds and the meter turns red. At zero, it's game over.

- Don't shoot the planet! Firing at your own world costs 5 shield layers.

- Survive a wave and the next one is faster and denser. By wave 11 the asteroids are at their deadliest.

- Beat a high score and enter your name on the table.

Controls

| Aim / fire | Mouse move / left click (touch on iPad) |

| Music on/off | M or the on-screen button |

| Sound effects on/off | S or the on-screen button |

| Backdrop / plain stars | B or the on-screen button |

| Pause / resume | P |

| Quit to title | Q |

| Reset high scores | H (title screen) |

| Exit | Esc |

Features

- Animated rotating asteroids in two varieties, big explosions, and a glowing planetary shield.

- Original title music, sound effects and voice-over.

- Persistent top-5 high-score table.

- Resizable window, scales cleanly to any screen

About

Gravity Force was first made in BlitzMax by me in March 2015 and has now been rebuilt in Java (libGDX) so it can live on Mac, Windows and iPad. I wrote the game as a challenge to actually get something done and completed within 1 month. I only just made it. 

Please note: This game is of its time. My development skills were a lot tamer back in those days so this is no epic game, by any means. I've wanted to release it for years as it's still pretty fun for a while and I have deliberately done only essential changes from the original game to get it working on multiple platforms. No gameplay elements have been changed at all.

Credits

- Game design & Coding: Tony Brice

- Title music loop (space4): Alapaus – freesound.org

- Some sound effects: SoundBible.com (public domain)

- Transition lettering: Clker.com; Game Over image: Wallpapercave.com (modified)

- Original tools: BlitzMax, Audacity, Bfxr, Sothink Logo Maker, Polyview

- Thanks: Aaron Thorne, Mark Sibly (R.I.P) and Jake Birkett

- Text font: DejaVu Sans Bold (free license)