Galaforce for Game Boy v1.0.0

Build: galaforce-1.0.0.gb (MBC1 + RAM + battery, 32 KB ROM).

At some point, we have to draw a line and get things out there rather than endlessly chasing 100% perfection! :-D This is version 1.0.0!

Changes

• New default high scores The defaults for each continue setting changed from 15000 / 30000 / 50000 / 60000 to __25000 / 50000 / 75000 / 100000.

Fixes

• **Smart bomb fires correctly on A+B. Previously A and B had to be pressed on the same frame. Now the bomb fires when both are held and at least one was pressed this frame. The fresh-press check stops the bomb from re-firing every frame while both buttons stay held. SELECT still triggers it as before.

• **HUD artifacts fix ** The LCD interrupt handler switches the background scroll and LCDC settings between the star field and the HUD. The change moves the top split to line 7 and makes both switches wait for HBlank, so they land cleanly on line 8 and line BOT_LINE. This should remove the visual glitches at the HUD boundary.

Galaforce for Game Boy v0.0.16

Build: galaforce-0.0.16.gb (MBC1 + RAM + battery, 32 KB ROM).

New

• Wave multipliers. Clear enough aliens in a pattern and the points you scored for that pattern are multiplied when it ends. Killing more than 80% of the aliens gives ×2. Killing every alien gives ×5. The multiplier is paid at the end of each pattern, not at the end of the zone.
• Multiplier display. The X2 or X5 text flashes beside the score when a multiplier is paid.
• Boss stage multiplier. The boss pattern is paid the same multiplier as any other pattern, so clearing it completely gives ×5.
• Dynamic boss hit scaling. The first boss (wave 3 / ZONE 04) takes 20 hits to destroy. Later bosses (waves 7, 11, 15 / ZONES 08, 12, 16) take 25 hits. Cosmetic explosions continue during the last 5 hits for both variants.

Changes

• Standard alien score. The four standard alien types score 10 points each. The boss scores 80 points.
• Spawned aliens count toward the wave. Aliens created by splitting or spawning are included in the wave total, so a pattern with spawning aliens can reach 100%.
• Cheat unlock sound. The cheat unlock sound plays at full priority, so it cuts the music.
• Enemy bomb speed. Fast enemy bombs move 2 or 3 px per frame (was 3 or 4), so they are a little slower but still faster than the slow bombs.
• Boss spawn logic updated. FillAlien in src/aliens.asm now uses wBossHits for type‑5 boss aliens instead of the static alien_hits table value.

Releases Galaforce for Game Boy v0.0.15

Release note (docs/RELEASE-v0.0.15.md):

Build: galaforce-0.0.15.gb (MBC1 + RAM + battery, 32 KB ROM).

New

• Boss explosions. Every bullet hit on the boss shows a full explosion with its sound. During the last 5 hits, explosions keep appearing one at a time over the boss, and the boss's death lasts longer.

Changes

• Smart bomb fix. A lost life no longer resets your smart bomb. Bombs you hold stay with you, and a new bomb is added only when the boss is killed (up to 2 held).

Galaforce for Game Boy v0.0.14

Build: galaforce-0.0.14.gb (MBC1 + RAM + battery, 32 KB ROM).

New

• Smart bomb. Press SELECT, or A and B together, to use a smart bomb. It hits every alien on screen once, and the boss once. Spawning aliens, which take two hits, survive a bomb with one hit left.
• Bomb supply. Each new life starts with one smart bomb. You can hold up to two. Destroying a boss gives you another.
• Bomb display. The lower status shows the bomb icon, with X2 when you hold two.
• Bomb sound and flash. A lower noise burst with a falling tone, and a short screen flash when the bomb goes off.
• New enemy bomb sprites. Enemy bombs are redrawn as glowing orbs.

Changes

• Boss zone formation. Zones 04, 08, 12 and 16 have a reworked boss formation. The boss pattern runs last, the lower alien row mixes two alien types, and the solo boss takes 20 hits and moves faster sideways.
• Black background by default. A white background can still be chosen on the options screen, and a saved choice is kept.
• Up to 7 lives. The starting lives default to 5, and you can now choose up to 7.
• Fairer default high scores. Each continue setting has its own starting high score: 15,000 with no continues, 30,000 with one, 50,000 with two and 60,000 with three. These apply until a real score is saved for that setting.
• Options screen. The OPTIONS title has its own shade and is centred. The menu values sit further left, and the ship and alien preview are a little higher.

Galaforce for Game Boy v0.0.13

Build: galaforce-0.0.13.gb (MBC1 + RAM + battery, 32 KB ROM)

Fixes: the four from your list, plus the lives total-ships fix, the last-life tune change, and the Zone 1 right-edge fix.

Enhancements:

• Hi-score per continue setting, with the defaults (30000 / 60000 / 75000 / 100000).
• No hi-score when a continue is used.
• No hi-score after a cheat start past ZONE 01.
• Continues default to off.
• Partial sprite-flicker improvement (ALSTEP = 9), marked as not fixing the boss wave.

Galaforce for Game Boy v0.0.11

Build: galaforce-0.0.11.gb (MBC1 + RAM + battery, 32 KB ROM)

Fixes

• Lost life music: the last-life sound is no longer cut by bullets or explosions while it plays. The Lost a Life tune cuts off the death explosion instead of being dropped while it plays.
• Music priority: a tune now takes the sound channels back and cuts any effect that is sounding. While a tune plays, sound effects are dropped, except FIRE and BOOM, which always start.
• Secret screen: on the options screen, DOWN DOWN UP UP SELECT opens a secret screen with a heart and sparkles, plus a sparkle sound.
• Fades: fades clear sprites at black, so game-over text and sparkles no longer carry onto the next screen.

Galaforce for Game Boy v0.0.10

Gameplay

• Player bullets move 4 px per frame (was 3).
• Alien bombs: slow bombs move a steady 1 px per frame; fast bombs alternate 3 and 4 px per frame.
• Wave 0 and wave 8 formation: the two vertical legs of the first formation's path are longer, so the aliens swing a little further up and down.

Sound

• Fire: full-volume, short click (was a slow attack that the next shot cut off).
• Explosions: kill explosions always play, cutting any sound still playing. Previously many were silently dropped.
• Hits: the hit sound on armoured aliens starts at full volume.
• Title: plays the attract-mode tune.
• Attract demo: silent (no music, no sound effects).

Title screen

• Flags: one flag per five levels, up to three, showing the highest wave reached since the console was switched on. Not saved between power-ons.

Tools and docs

• README.md: screenshots replaced by two demo GIFs, light and dark background.
• tools/makegif.py: BG=0 records the dark-background GIF.
• Static screenshots in docs/screenshots/ have been removed.

Galaforce for Game Boy

A Game Boy (original DMG) port of Kevin Edwards' 1986 BBC Micro shoot-'em-up Galaforce. It's written in SM83 assembly and ships as a 32 KB ROM with battery-backed saves (galaforce-0.0.9.gb). It's a personal project and not for distribution.

Game

• All 16 waves, with the original formations and flight paths, and a boss at the end of waves 4, 8, 12 and 16.
• Sprites redrawn for the 4-shade screen, with each alien type distinct in contrast.
• Music and sound effects recreated in the style of the original.
• The title screen has the scrolling starfield and a shine across the logo. After about 13 seconds idle it starts a self-playing demo.
• The score is at the top and the lives at the bottom, as in the original.

Options (saved to battery RAM)

• Lives: 1 to 5.
• Continues: 0 to 3, default 1. At game over, if you have continues left, it asks CONTINUE? YES/NO. YES refills your lives, keeps your score and replays the wave.
• Background: black or white (white is the default).
• Cheat: on the options screen press Up, Up, Down, Down, Select to unlock a WAVE row (1 to 16, not saved).