Sonic Chaos/sandbox
From Sonic Retro
Credit goes to Hivebrain for the SMS notes, Ravenfreak for the GG notes, and nineko for the music hacking notes.
Note: Most compressed art and some uncompressed art is located at the same offsets in the GG version.
Master System ROM contents
| Offset | Description |
|---|---|
| $8D8-$AD0 | ASCII - Level Select |
| $AF6-$C28 | ASCII - Sound Test |
| $10000 | Uncompressed art - Sonic (Same in GG) |
| $13D00 | Blank |
| $14000 | More uncompressed Sonic art (Same in GG) |
| $16940 | Uncompressed art- Tails (Same in GG) |
| $17680 | Uncompressed Art - MGHZ Pole Climber Boss (Same in GG) |
| $17EA0 | Blank |
| $18000 | Uncompressed art - More tails |
| $1BC80 | Blank |
| $1C000 | Uncompressed art- More Sonic |
| $1FA40 | Compressed Art - HUD & Numbers (excluding icons) |
| $1FC6E | Blank |
| $20000 | Uncompressed Art - Even More Tails |
| $23340 | Compressed Art - Icons, Spikes, 16x16 blocks, HUD & Numbers (this stuff gets overwritten in vram) |
| $23B92-$24000 | Blank |
| $24440 | Uncompressed Art - Signpost (124 tiles) |
| $253C0 | Compressed Art - cone enemy (SEZ) |
| $255A0 | Compressed Art - flying enemy - facing right (THZ, GPZ, EEZ) |
| $25690 | Compressed Art - flying enemy - facing left (THZ, GPZ, EEZ) |
| $25780 | Compressed Art - beetle enemy (GPZ) |
| $25950 | Compressed Art - spring enemy (SEZ) |
| $25AB0 | Compressed Art - Motobug (THZ) |
| $25CD0 | Compressed Art - Spring Enemy (MGHZ) |
| $25EE0 | Compressed Art - coconut bomb (MGHZ) |
| $26030 | Compressed Art - spring |
| $261C0 | Compressed Art - THZ Platform |
| $262C0 | Compressed Art - GPZ Platform |
| $26370 | Compressed Art - SEZ Platform |
| $26470 | Compressed Art - MGHZ Platform |
| $26570 | Compressed Art - APZ Platform |
| $26630 | Compressed Art - EEZ Platform |
| $26720 | Compressed Art - Shooting Star (GPZ) |
| $26780 | Compressed Art - oil splash (MGHZ) |
| $26840 | Compressed Art - Pogo Spring |
| $26A50 | Compressed Art - Bomb enemy (EEZ) |
| $26B60 | Compressed Art - Water Surface Wave |
| $26D20 | Compressed Art - Laser Canons (EEZ) |
| $26F10 | Compressed Art - Oil Splash (duplicate, MGHZ) |
| $26FD0 | Compressed Art - Unknown/unused (EEZ) |
| $26FF0 | Compressed Art - Sliding Cart (EEZ) |
| $27090 | Compressed Art - Harpoon (APZ) |
| $27150 | Compressed Art - Penguin enemy (APZ) |
| $272C0 | Compressed Art - Bubbles (APZ) |
| $273E0 | Compressed Art - Spring (final frame?) |
| $274A0 | Compressed Art - Splash (APZ) |
| $27600 | Compressed Art - Robotnik (Intro) |
| $27B60 | Compressed Art - Tails (Intro) |
| $27D90 | Compressed Art - Sparkles (Good Ending) |
| $27EC0 | Uncompressed Art - "TM" (4 tiles) |
| $27F40 | Blank |
| $28000 | Uncompressed Art - Tails (75 tiles, includes looking up, flying, and inside cart from EEZ) |
| $28940 | Uncompressed Art - THZ Motobug Boss (72 tiles) |
| $29280 | Uncompressed Art - GPZ Caterpillar Boss |
| $29F80 | Uncompressed Art - SEZ Spring Boss |
| $2A840 | Uncompressed Art - APZ Pod Boss |
| $2B8C0 | Blank |
| $2C000 | Uncompressed Art - Final Boss |
| $2FE40 | Blank |
| $2FD00 | Uncompressed Art - Smoke Puff from Enemy/Monitor |
| $30000-$33FFF | Blank |
| $354BC | Uncompressed Art - Signpost (Final Frame) |
| $48000 | Level Layout - THZ1 |
| $48BA9 | Level Layout - THZ2 |
| $49815 | Level Layout - THZ3 |
| $49C25 | Level Layout - GPZ1 |
| $4AA00 | Level Layout - GPZ2 |
| $4B987 | Level Layout - GPZ3 |
| $53460 | Level Layout - SEZ3 |
| $54000 | Level Layout - SEZ1 |
| $54CC8 | Level Layout - SEZ2 |
| $559D4 | Level Layout - MGHZ1 |
| $566B8 | Level Layout - MGHZ2 |
| $572FB | Level Layout - MGHZ3 |
| $57AF3 | Level Layout - APZ3 |
| $5C000 | Level Layout - APZ1 |
| $5C7C1 | Level Layout - APZ2 |
| $5CF3A | Level Layout - EEZ1 |
| $5DB73 | Level Layout - EEZ2 |
| $5E853 | Level Layout - EEZ3 |
A note on the loop motion data. Loop motion data is split up into four parts in Sonic Chaos. 2 arrays handle the camera, 2 handle player movement. The full array for when the player goes through the loop forwards is located from $34000-$346AD. The array for when the player goes forwards through a loop is located at $346B0. Camera movement for when the player goes through the loop backwards is located at $34A48. Like in Sonic 2 (8-bit) you can change this to anything, keep in mind to have it look right you need to edit not only the player movement data, but the camera movement as well.
Game Gear ROM contents
| Offset | Description |
|---|---|
| $1F7C0 | HUD Numbers and Km/H compressed art |
| $1FD80 | Uncompressed art - Tails (430 tiles) |
| $40A70 | Intro/THZ Tiles |
| $41F4A | GPZ Tiles |
| $5FF00 | Sonic Tripping (Uncompressed, 66 tiles) |
| $6A8B7-$6AAB6 | ASCII Credits text |
| $74580 | Uncompressed Art - Rings (16 tiles) |
| $74780 | Uncompressed Art - Unknown (GPZ Stars?) |
Music editing
| Song ID |
Location in the Master System 1.2 version |
Location in the Game Gear 1.0 version |
Usage in the Master System 1.2 version |
Usage in the Game Gear 1.0 version |
|---|---|---|---|---|
| 81 | 9169 | 91B7 | MS Turquoise Hill | GG Turquoise Hill |
| 82 | 963F | 975F | Character Select | Character Select |
| 83 | 9793 | 985D | MS Gigalopolis | MS Gigalopolis |
| 84 | 9CE8 | 9DB2 | Invincibility | Invincibility |
| 85 | 9EB2 | 9F7C | Rocket Shoes | Rocket Shoes |
| 86 | 9F7A | A044 | Unknown | Unknown |
| 87 | A005 | A0CF | Game Over | Game Over |
| 88 | A0A5 | A16F | Stage Start | Stage Start |
| 89 | A152 | A21C | Stage Completed | Stage Completed |
| 8A | A1E1 | A2AB | Chaos Emerald | Chaos Emerald |
| 8B | A23D | A307 | Final Boss | Final Boss |
| 8C | A948 | AA12 | Boss | Boss |
| 8D | AF69 | B033 | Good Ending | Good Ending |
| 8E | B634 | B6FE | Unused | Unused |
| 8F | B6C4 | B78E | Special Stage | Special Stage |
| 90 | B8EB | B9B5 | MS Intro | GG Electric Egg Act 3 |
| 91 | BEF6 | BFC0 | Sleeping Egg | Sleeping Egg |
| 92 | C3DD | C4B4 | Mecha Green Hill | Mecha Green Hill |
| 93 | C8B6 | C98D | MS Aqua Planet | GG Aqua Planet |
| 94 | CFDD | D0F9 | Continue | Continue |
| 95 | D206 | D322 | Electric Egg | Electric Egg |
| 96 | D7DC | D8F6 | Death | Death |
| 97 | D881 | D99B | Boss Defeated | Boss Defeated |
| 98 | D91C | DA36 | Try Again | Try Again |
| 99 | D991 | DAAB | Title Screen | Title Screen |
| 9A | DBCA | DCE4 | Bad Ending | Bad Ending |
| 9B | DE54 | DF6E | Blank | Sunset Park 3 |
| 9C | DE6E | E52D | Blank | GG Gigalopolis |
| 9D | DE88 | EBCC | Blank | GG Intro |
| 9E | DEA2 | ECF4 | Blank | GG Special Stage |
| 9F | DEBC | F16F | Blank | Speed-Up Shoes |
RAM editing
While most of the RAM addresses are the same from S2 SMS, some are different. Listed bellow is one that's not in S2.
| Offset | Description |
|---|---|
| $D3A1 | Flying Counter, this is set to 300 and counts down to zero. Determines how long Tails can fly. Setting
this to a different value can make him fly constantly until he colides with objects and or the floor. |