Proto:Knuckles' Chaotix/Sonic Crackers

This is a sub-page of Proto:Knuckles' Chaotix.

File: Sonic Crackers (Prototype).bin (1 MB) (info)

Sonic Crackers (referred to as Sonic Studium in the ROM header) is a very early prototype build of Knuckles' Chaotix. Its name comes from the peculiar ASCII-art title screen that looks like it was thrown together in 5 minutes. Sonic Crackers is thought to be an engine test, composed of different game engines swapped out using RAM coding.

The game stars Sonic and Tails, held together by Combi rings as seen in Chaotix. Like the final game, Sonic can pick up Tails and throw him up to make it easier to reach higher platforms. Crackers contains only two proper side-scrolling levels in addition to two overhead levels that did not make it into Chaotix. There are no sound effects at all during gameplay and no Badniks to be found, although there are spikes and you lose rings when hitting them (even though you have none). The music mostly consists of early versions of Chaotix tracks.

The date on the lower-right of the title screen reads "19940401", which led to much debate on if the title screen or the ROM as a whole was an April Fool's joke. The later discovery of several Chaotix prototypes, especially the 1207 build, proved that this was not the case. Also, when viewing the ROM through a hex editor, the date "JUL.1994" can be seen; while this would suggest that a bit of work had been done since April, this is unlikely, as among the unused graphics in a prototype build of Yuu Yuu Hakusho: Makyou Toitsusen (dated June 1994) are Field sprites for Tails that are not in this build.

Much later, various Crackers graphics were used for Egg Gauntlet Zone in the 2013 version of Sonic 2, although the Zone was never normally accessible and both it and its assets were later removed.

General

As a very early prototype, Sonic Crackers is extremely incomplete and unpolished. However, the basic mechanics that serve as the basis of Knuckles' Chaotix are present at this point and similar to how they ended up in the final.

The player controls Sonic and Tails, who were cut from the final game. However, the pair were not entirely scrapped - Sonic was retooled into Chaotix's Mighty the Armadillo by the 1207 prototype, as evidenced by the two's sprites being practically identical. Meanwhile, Tails was cut sometime between this prototype and the 1207 prototype, though his behavior was functional until the 0119 prototype.
The game is split between four playable levels: "Attractions", side-scrolling levels similar to those seen in previous Sonic games, and "Fields", overhead levels that have no collision detection. While Fields were cut by the 1207 prototype, like Crackers, Chaotix calls its levels Attractions.
The primary game mechanic of Chaotix - the rubber band-like Combi rings connecting the two playable characters - has been implemented at this point. While it's similar to how it ended up in the final, there are some key differences owing to this prototype's incompleteness:
- The A, B, C, X, Y, and Z buttons all share the same functionality, causing Sonic to jump, Tails to stop moving, and, if close enough, Sonic to pick up Tails (and throw him). These functionalities were retained in Chaotix, except that the jumping and holding buttons were separated and a recall button was added.
Pressing "Start" allows the player to move Sonic and Tails' X and Y positions with the D-Pad, much like the debug modes of prior Sonic games.
The Attractions are mostly devoid of objects; the only objects that the player can interact with are springs (which work as they normally do in Sonic games) and spikes (which cause the player to drop rings even though there are no rings to collect). Players cannot die, although the level will end once the in-game timer reaches a certain point.
Physics are extremely rudimentary; Sonic and Tails are not affected by gravity and can walk on walls and ceilings with no momentum.
The soundtrack comprises early versions of Chaotix tracks. There are no sound effects in-game, though sound effects are present in the ROM.

Levels

There are four playable levels, which are accessible either by pressing Start on "1P START" or "2P START" on the title screen or by using the "SELECT" menu.

Attraction Levels

Starting Level and World 2 Levels

An industrial-themed level. This is the only level with an obstacle which causes harm to the player (spikes), which in turn makes this the most complete level of this build. The palette and music changes each time the level is entered, which indicates that time of day was already planned at this point complete with four different themes, themselves early versions of Chaotix songs (Walkin', Hyper-Hyper, Evening Star, and Moonrise). Due to a vaguely similar aesthetic and the goal of this level being to reach the top, this level is speculated to be a very early version of Techno Tower from Chaotix.

When the timer reaches 3 minutes, or when the top of the level is reached, the Game Over sound plays and a Field level is entered.

World 2, Attraction 1
World 2, Attraction 2
World 2, Attraction 3
World 2, Attraction 4

(Source: Sonic Retro)

World 1 Level

A circus/carnival-themed level which, rather than having a definite end, loops. The collision detection is glitchy and makes the floor difficult to walk on when entering the normal way. Each time the level loops, the collision gets more and more broken. The best way to play it is by entering it using the Level Select, which will make the ground solid (Tails seems to be able to walk on the ground without any trouble, though). The characters' arms and Tails' tails will glitch sometimes when they are on slopes. If you go far enough with debug mode, strips of garbage data spawn at the bottom of the level. Like the World 2 Attraction, this level is thought to be a very early version of Chaotix's Speed Slider due to the similar aesthetic.

The music of this level is an early version of Electoria, and Game Over activates after 1 minute. You cannot die from falling into a pit, and are simply stuck there unless there is garbage data or you debug your way out.

(Source: Sonic Retro)

Worlds 3-7 and Premium 1-2

No work has been done on these. Trying to enter them shows the title card and plays the World 2 music for a few seconds before immediately giving you a Game Over and beginning a Field level.

(Source: Sonic Retro)

Special Stage

Present on the Level Select menu, but no work has been done on this either. Unlike the above, however, selecting it causes the game to crash.

Field Levels

A pair of overhead field stages which are very incomplete and have no collision detection. The music is an early version of Electoria.

To exit these stages, simply pause and press any button. The game will then load an Attraction of the World it is on.

Unused World 2 Field Level Palette Cycle

The second Field Level in Sonic Crackers has a bug in one of its color palette cycles. The color palette cycle incorrectly uses color palette line 2, instead of 3 which is the foreground. However, by using the codes 008570:D43C and 0085DC:D43E (or HWCT-BKXT and H4CT-BK06), the intended effect can be restored.

Unused Chunks

There are a ton of unused stage chunks.

World 1

Some of these chunks, while unused in the level layout itself, appear as part of the garbage data found at the bottom of the level in the loopback.

07
0A
0B
0C
0E
17
19
1A
1C
1D
20
24
2A
2C
2D
30
38 - Appears in the loopback.
39 - Appears in the loopback.
3A - Appears in the loopback.
3C - Appears in the loopback.
3D - Appears in the loopback.
3F - Appears in the loopback.
42 - Appears in the loopback.
43 - Appears in the loopback.
45
47
48
49
4B
4C
50
51
52
53
56
57
58
5A
5C
5D
5E
60
61
63 - Appears in the loopback.
64
66
67
68
6A
6B
6C
6E
6F
70
71
72
73
74
75
76
78
79
7A
7B
7C
7D
7F
80
87
88
89
8A
8B
8C
8D
8E
8F
90
91
92
93
94
95
96
97
98
99
9A
9C
9D
9E
9F
A0
A1
A2
A3
A6
A7
A8
A9
AB
B0
B1
B4
B7
B9
BC
BE
C0
C1
C5
C8
C9
CA
CD
D2
D3
D8
D9
E2
E3

World 2

This stage has a lot more unused chunks than used ones.

Foreground

0E
0F
10
11
17
18
19
1A
1B
1C
1D
22
24
25
27
28
2A
2B
2D
2F
30
33
37
39
3B
3F
41
42
44
45
46
47
48
49
4A
4B
4C
4D
4E
4F
50
51
52
53
54
55
56
57
58
59
5A
5B
5C
5D
5E
5F
60
61
62
63
64
65
66
67
68
69
6A
6B
6C
6D
6E
6F
70
71
72
73
74
75
76
77
78
79
7A
7B
7C
7D
7E
7F
80
81
82
83
84
85
86
87
88
89
8A
8B
8C
8D
8E
8F
90
91
98
99
9A
9B
9C
9D
9F
A0
A1
A2
A3
A4
A5
A6
A8
A9
AA
AB
AC
AD
AE
AF
B0
B1
B2
B6

Background

A sky with stars goes unused.

0C

Unused Sprites

To do:

Knuckles and Vector's line is present in the palette; that should probably be documented.

Sonic Crackers contains a fair amount of unused sprites. Notably, many of Sonic's ended up getting repurposed for Mighty's in Knuckles' Chaotix.

Artwork	Name	Description
	Title Screen Font	Characters that are loaded into the VRAM for the title screen and menus but are not used, including a complete set of lowercase letters.
	Field Jumping Sprites	Jumping animations for Sonic and Tails in the Field levels. Sonic and Tails can't jump in the Fields, rendering these unused.
	Hold	Sonic and Tails' hold sprites, which go unused even though the hold mechanic has been implemented at this point. Notably, Sonic looks different from how Mighty would end up in his hold pose.
	Throwing	Like the hold sprites, these go unused even though throwing is present at this point. Sonic's sprites match up with Mighty's in the final, aside from Mighty turning his head more. Additionally, Tails' throw appears to show him stumbling, which lines up with him having the weakest throw in the other Chaotix prototypes he's still functional in.
	Wall Kick	Sonic performing a wall kick. While the ability is not coded in at this point, all the necessary frames are present, showing that the wall kick mechanic was planned before Sonic became Mighty. Additionally, these sprites line up perfectly with Mighty's wall kick sprites (both the used and unused ones) in the final.
	Climbing	Sonic hanging and climbing up a ledge. This is one of only two sprites that didn't make it into Chaotix to be adapted for Mighty. It is unclear how this would have been used, though it's possible that it was another ability planned for Sonic/Mighty.
	Hanging (?)	What appear to be hanging sprites; like the climbing sprites, Sonic's sprite was not adapted for Mighty in the final. Sonic's was probably used as part of his climbing animation, but the presence of an equivalent sprite for Tails suggest it might've been for something else.
	Flying/Tired	Tails' flying and tired sprites. The flying sprite is the same as Sonic 2 minus the arm, while the tired sprites are unique. Modified versions of the tired sprites were later used in the Taxman/Stealth Retro Engine remakes of Sonic CD, 1, and 2.
	Sparkle Effects	Various sparkle effects that are loaded into VRAM during attraction levels. The second palette line fits them the best.
	Ring Sparkle	Sparkles normally seen when collecting Rings. While Rings are dropped when touching spikes, they cannot be collected.
	HUD Objects	Various HUD objects, including "Combi" and "Limits" (both of which remained through the final Chaotix). Given that Chaotix uses Limits for the Special Stage, the red objects on the right were most likely for Crackers' Special Stage (which is not actually present in this build).

Hardware Issues

The game will crash on a real Mega Drive/Genesis console if the player does not skip the Sega screen quickly enough or stays at the title screen for too long. This is due to the sound driver (which is held on and controlled by the Z80 sub-processor) - if it isn't given a music track ID to process quick enough after being set up, the game will fail. To fix this, open the ROM in a hex editor and go to offset $0052B7, then replace 21 05 1C 7E with 11 00 00 00.

When bypassing the crash stated above and obtaining access to the other selections in the menu, the game can crash in the Level Select option named "SELECT". When selecting the "PREMIUM1 - ATTRACTION" selection, the game crashes with a plain blue screen. The same happens when selecting "PREMIUM1 - FIELD", which will lead to the World 2 Field stage first, and will happen upon pausing and pressing A.

(Source: Sonic Retro)

The Game's Name

The ROM header says the game is "Sonic Studium", as opposed to the "Sonic Crackers" on the title screen.

The ROM header name should be "Sonic Stadium". This is due to a transliteration error into Japanese, where it became スタジアム (sutajiamu). Japanese has no "di" syllable, so "ji" is used in its place. The short vowel "a" in Japanese is pronounced as in the English word "father". As such, スタジ would sound very much like the English word "stud". An excerpt from the Sonic Mars script shows "Sonic Stadium" as a title under the "Future SEGA" products category, along with "Sonic 3+". The 1207 Chaotix prototype has unused graphics spelling out "Sonic Crackers S32X", indicating that the official name was changed after Mars was renamed to Super 32X.

Similarly, the name on the title screen (and by extension in the aforementioned Chaotix graphics) should be "Sonic Clackers". Japanese doesn't distinguish between Ls and Rs, and a result the name is a result of a cyclical transliteration error (Sonic Clackers -> ソニッククラッカー -> Sonic Crackers).

(Source: Sonic Retro)

Audio

Sounds

To do:
Upload the unused sound effects, maybe?

While the game doesn't use sound effects, there's a number of them in the ROM, mostly (if not entirely) brought over from previous games.

00 - Sonic CD jumping SFX.
01 - Sonic 1 end-of-Act/Special Stage "tally finished" SFX.
02 - Unknown, possibly early spike SFX.
03 - Sonic 1 bomb explosion SFX.
04 - Sonic 1 skidding SFX.
05 - Sonic 1 Ring loss SFX.
06 - Sonic 1 Ring collect SFX.
07 - Sonic 3 & Knuckles Badnik destroyed SFX.
08 - Sonic 1 spring SFX.
09 - Sonic 1 checkpoint SFX.
0A|0F - Likely placeholders.

PCM

Hidden deep in the ROM at 0x21672 and 0x22BEE are unused samples of a woman yelling "Let's go! Hey!". Where these samples would be used are an mystery; none of Crackers and Chaotix's music ever use vocal samples (and by Ringstar they're completely gone) and the only samples used are drums.

Hex Offset	Sound
`0x21672`
`0x22BEE`

(Source: PACHUKA, properly decoded by pobert-eii)

Music

To do:
Analyze the tracks, comparing them to their Chaotix counterparts.

As previously noted, the music of Crackers mostly consists of early iterations of Chaotix songs. All of the tracks feature different percussion to their final counterparts - the Crackers versions just utilise the Mega Drive's DAC channel for percussion, whereas the Chaotix versions were reworked to make use of the 32X's PWM channels instead, with several changes and embellishments made to the percussion in the process.

Name	Sound ID	Notes
Electoria	`81`	The most different to its final counterpart. While the backing is very similar to the final version, the main melody has been changed completely - the chorus of the Crackers version echoes the same basic melody as the other stage music present in this build, whereas the Chaotix version drops this in favour of a unique melody instead.
Walkin'	`82`	As the Crackers DPCM samples have been replaced with the 32X's PWM samples (which allow for additional sounds in one channel), there's a additional maraca in the drumline. The lead melody has gained a additional echo channel which is hard to hear at first.
Hyper-Hyper	`83`
Evening Star	`84`	The percussion track(s) were greatly changed to sound more dynamic.
Moonrise	`85`