Proto:Sonic the Hedgehog 2 (Genesis)/Nick Arcade Prototype
This is a sub-page of Proto:Sonic the Hedgehog 2 (Genesis).
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This prototype is documented on Hidden Palace.
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Download Sonic the Hedgehog 2 (Nick Arcade Prototype)
File: Sonic The Hedgehog 2 (Nick Arcade Prototype).bin (1 MB) (info)
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The Nick Arcade prototype of Sonic the Hedgehog 2 is a very early build with many visible remnants from Sonic 1, such as level names and music. It is very incomplete, with missing enemies and levels plus graphical glitches everywhere. However, the basic layouts for a few levels have been completed, and Tails has been implemented.
The prototype was dumped by drx and released to the public on November 7, 2006. The rom itself was built sometime in late May, based on development documents released by Tom Payne. It was given its name due to its similarity to a version of Sonic 2 that was showcased on the last four episodes (81-84) of the game show Nick Arcade, as this build appears to be very close to (if not exactly the same as) the build used on the show; two of the episodes can be seen here and here, and all four can be viewed on Paramount+ in the United States.
As an additional note, this is the only known Genesis cartridge to use a holographic label. According to a tweet from ex-Sega of America staffer Al Nilsen, the idea was scrapped as it would make production costs for the cartridge itself very high.
Contents
Sub-Pages
Zone Differences
 | Green Hill The hills get a bit quirky at night... |
 | Chemical Plant Pink buildings. |
 | Hidden Palace It's not garbage data here! |
 | Labyrinth Remnants Oh no... |
 | Emerald Hill The only beatable Zone. |
 | Hill Top Hope you like purple! |
 | Other Final Zone, the ending scene, and the Special Stage. |
Leftover Content
 | Leftovers Oh boy, there's a lot here. |
 | Symbol Tables Two massive blocks of compiler information from earlier builds leftover within the padding. |
General Differences
- At this point in development, Tails is quasi-independent: Player 2 is able to control Tails, except he will also follow Sonic. Further, Tails cannot complete a level on his own, since the game only loads the signpost when Sonic approaches it. If Tails gets hurt, he can lose rings for Sonic. The AI is also much simpler: Tails copies Sonic's moves and makes no attempt to keep up with him.
- 2-Player mode is even less complete, due to all sorts of odd glitches and not being enabled for every Zone.
- Invincibility doesn't show the star effect, though the music is still played. The music and invulnerability last until the end of the Act.
- There is a mechanic where Sonic rebounds off walls if he runs into them at high speeds, using sprites that became unused by the Simon Wai prototype. The sprite of him getting up would later be polished and reused for when Sonic leaves his "lying on ground" idle animation.
- The spin dash is a work-in-progress, as Sonic and Tails can only charge it once. Further, the sound for when Sonic spins in Sonic 1 is heard as there is not yet a specific sound effect for the spin dash.
- The spike damage behavior works the same way it does in Sonic 1.
- The ground speed cap from Sonic 1 is still present.
- The explosion sprites are the ones in Sonic 1.
- Debug mode follows the logic of Sonic 1.
- Sonic's speed and velocity don't reset when exiting debug.
- When Sonic is hit without rings, he'll only be knocked back; The only way for him to lose a life is by drowning/falling into a bottomless pit.
- Sonic cannot enter debug while he is being knocked back.
- Sonic cannot enter debug when he is in his death animation.
- Entering and exiting debug while submerged will not reset Sonic's underwater timer.
- Sonic retains his land speed if entering debug from water, and exiting to land.
- If Sonic has passed a signpost, entering and exiting debug will not allow the player to regain the ability to control him.
- Spawned monitors can only be broken once per life/Act.
- Locking on this prototype with Sonic & Knuckles will unlock the full Blue Sphere game.
- The timer resets to 9:00 before hitting 9:59, allowing the player to test stages for extended periods.
- If Sonic and Tails are both hit at the same time while carrying at least one ring, an overabundance of rings will pop out regardless of how many they actually possess.
- The screen doesn't scroll up or down when you look up or down for a certain period of time.
- The down-pointing spring has some weird behavior that appears to have been disabled starting with the September 14th build: If Sonic hits such a spring and uses his death sprite for it, he will roll into a ball once he reaches the ground, and can shoot far from a quarter-pipe, stick to flat ground surfaces, and even clip below the floor into his death.
- The sound driver is completely unaltered from Sonic 1, even the functions are in the same positions as they were in that game.
 | This needs some investigation. Discuss ideas and findings on the talk page. |
Title Screen
The title screen is different, with a particularly well-known design: not only does it appear in the Simon Wai build, it also appears in the final game's instruction manual, as well as the Master System and Game Gear versions. The version seen in the manual is the same as the second picture above.
| Nick Arcade to August 21, 1992 | September 14, 1992 to Beta 4 | Beta 5 onward |
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The title screen uses the background for Emerald Hill Zone instead of the custom background used in Beta 5 onward. It uses a slightly darker palette than what's used in the actual level (notice the blues in the clouds and water), and the left-most cloud seen in the level background is missing.
| Title Screen | Level |
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Cheat Codes
- Level Select - Up, Down, Down, Down, Down, Up, A + Start.
- 2-Player Mode - On the Level Select, press B + Start on any level.
- Debug Mode - C, C, Up, Down, Down, Down, Down, Up, A + Start. Debug can also be enabled with Pro Action Replay code FFFFFA:0001. As with Sonic 1, C merely needs to be pressed twice before the final input of Up.
- Debug Mode and Level Select - Up, Down, Down, Down, Down, Up, UDLR, Up, Down, Down, Down, Down, C, C, Up, A + Start. "UDLR" simply means to press any direction on the D-Pad to reset the cheat detection code. Unlike the final, where both Debug Mode and All Emeralds can be enabled by playing 19921124126 on the Level Select screen, the last Up of the Level Select code cannot "overlap" with the first Up of the Debug Mode code.
Attract Mode
The game cycles through four demos: Chemical Plant, Emerald Hill (2P), Hidden Palace, and Hill Top. This would be the last time that new demos were recorded for the game before the final build; all other prototypes use the inputs from this build.
| Demo 1 | Demo 2 |
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| Demo 3 | Demo 4 |
Changed Graphics
Sonic & Tails
| Sonic 1 | Nick Arcade/Simon Wai | August 21 onward |
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Sonic's sprite in the Nick Arcade and Simon Wai builds is much closer to his design in Sonic 1. His idle frame is identical except for shorter shoes and an added shine on the side of his head. The August 21 build changes the shape of Sonic's eyes and adds some shading to the top of the eye.
| Nick Arcade/Simon Wai | August 21 onward |
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Sonic's blinking frame in the earlier prototypes is a bit strange. It looks less like his eyes are closed and more like his pupils are all all the way at the bottom of his eyes. The final game thankfully adds flesh-colored eyelids to the sprite.
| Nick Arcade/Simon Wai | August 21 onward |
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Sonic's eye design wasn't updated in all frames: In his looking up and crouching down animations, they just added shading to the top of the eye without actually changing its shape.
| Nick Arcade/Simon Wai | August 21 onward |
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Sonic's walking animation has 12 frames of animation in earlier versions compared to the 8 frames seen in the final sprite. The minimum animation speed is also double what it is in the final game, and shows much more of the American "mohawk" design.
| Nick Arcade/Simon Wai | August 21 onward |
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One of the easiest to see changes: In the Nick Arcade and Simon Wai builds, when Sonic runs, his shoes and legs go into a cartoony blur. This was toned back in the final version to as it was in Sonic 1, just affecting his sneakers. Oddly, these early sprites were used in a teaser for Sonic 4 - Episode I. This kind of sprite was later reused in Sonic Mania whenever he or Knuckles are going full speed.
| Nick Arcade/Simon Wai | August 21 onward |
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Sonic's skidding animation is very different here. It starts out with a new, unique beginning before reusing a few frames from Sonic 1, then turns around and starts pushing in the other direction. The final two frames will loop until Sonic either stops completely or does a different action. The beginning of the animation was later reused in Sonic Mania.
| Sonic 1 | Nick Arcade/Simon Wai | August 21 onward |
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In the original game, Sonic's body moves but his hands didn't. In the early prototypes, his hands move but his body stays level. The final sprite splits the difference and moves the body and hands in different frames. Oddly, there is orange coloring on his shoes, because the sprites were based off of Sonic 1's sprites plus a minor coloring oversight. This orange shade would be the darkest shade of red if given the first game's main palette.
| Sonic 1 | Nick Arcade/Simon Wai | August 21 onward |
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The balancing animation is just a faster version of the Sonic 1 animation with added head shine and an orange mouth, due to sprites being based off of Sonic 1's sprites plus, just like the pushing animation, an oversight in the sprite's coloring. The final game adds four new balancing animations based on how far Sonic is from the edge and whether or not he's facing the edge.
| Nick Arcade/Simon Wai | August 21 onward |
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The only difference in Tails' graphics is an added shine to his spinning sprite.
Badniks
| Nick Arcade/Simon Wai | August 21st onward |
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Buzzer's sprite was touched up a bit between the Simon Wai and August 21st builds: Its head was redesigned to be less ant-like, more detail was added to the abdomen, and the jets were straightened out.
| Nick Arcade to August 21st | September 14th Prototype | CENSOR onward |
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Crawl's early sprite (0xA9580 in the ROM) is very different from its final design, lacking any kind of walking animation and only able to put its shield up in one direction.
Other Sprites
| Nick Arcade | CENSOR onward |
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All three signposts were originally symmetrical. Only Robotnik's remained that way.
| Nick Arcade | Simon Wai onward |
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At 0xA4368 is a graphic for a fireball. The Hill Top boss in the final game can shoot out fireballs, but those fireballs grow and shrink in size and have three frames of animation. The older sprite would probably be animated like the fireballs in Sonic 1's Marble Zone: 
Unused Graphics
Sonic
| Graphic | Frame ID | Description |
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0A-0B | Unused sprites of Sonic turning. The developers might have intended to have Sonic turn when changing direction instead of instantly facing the other way, or possibly a winning pose similar to Sonic's goal sign in this build. |
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40-43 4C-4F 58-5B 64-67 |
Sprites for Sonic moving even faster than normal. |
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44-47 50-53 5C-5F 68-6B |
More sprites for Sonic presumably hitting max speed. Look at him just sticking his head out there. Tails does have a full-speed animation, though the only change is his two tails using only two sprites. |
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7B-7D | An unused animation of Sonic pulling, or possibly carrying, something. Puzzle elements involving pulling or carrying things may have been planned for.
Interestingly, one of the sprites from this animation would be used in, of all things, page 46 of the book The History of Sonic the Hedgehog, which was officially licensed by SEGA. |
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8B-8C | An unused animation of Sonic balancing on a ledge. This was probably meant to be used when the player was just a few pixels from falling. It looks similar to the on-the-edge balancing animation seen in Sonic the Hedgehog 3. |
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While Sonic's 45° run sprites don't have his spikes changing, tiles do exist for it in the ROM. This is not applied to any sprite. |
Other
| Graphic | Offset | Compression | Description |
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0x27098 | None | A background element depicting a cavern obscured by stalagmites (and stalactites), not a weird purple blob. Used in an early version of the Hidden Palace background seen in a mockup screenshot, but not in any real (known) prototype. It is grouped in with animated tile graphics. |
 
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0x27798 | None | Animated tiles that aren't loaded in any zone, but seem to match the Chemical Plant level palette pretty well. Source code leftover from an earlier build of Sonic 2 suggests that these were meant to be loaded in VRAM in Chemical Plant Act 3 for the boss. The Chemical Plant boss was referred to as "vacume" in the leftover source code and was removed for some reason, with all its unique code being deleted from this build. |
 
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0x27DD8 | None | More animated tiles using the Chemical Plant palette. There aren't any foreground tile-based propellers or water in the final game. |
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0xA44A0 | Nemesis | What looks like a burning piece of something or other. Early concept art shows a Buzzer-like Bee enemy that could destroy bridges by burning them with fireballs - this could be a remnant of that idea. |
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0xA4BCE | Nemesis | This is the Hill Top one-way gate. It's identical to the one in the final game, it just hasn't been coded yet. |
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0xA4F56 | Nemesis | Inside the graphics for Hidden Palace Zone's waterfall objects are these tiles, which were clearly meant to connect to the Water slides. They have no known mapping data and were likely never actually used before being scrapped. |
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0xA5826 | Nemesis | Graphics for a Hidden Palace object, possibly a floating platform. It's not clear how they would be assembled. A similar object is seen in the 2013 rerelease as an aquatic platform. Source code labels refer to the graphic as cork08cg. |
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0xA59C0 | Nemesis | A dissipating cloud. Source code labels refer to the graphic as kemuri0dcg, suggesting it's for Chemical Plant Zone. |
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0xA5D9E | Nemesis | The standard Sonic 2 switch has already been drawn and digitized by this point, it just hasn't been coded yet. |
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0xA8CA0 | Nemesis | A spinning metal ball. This was seen in some early concept art - it would act as an obstacle by continuously bouncing around the floor in a high arc. Interestingly code is implemented for this object in the Alpha build. It would bounce in a random direction harming the player if touched, it would change its direction after touching a wall. This can be found in the 2013 rerelease via Debug Mode, though it uses a different palette and explodes once floating above the player's head. |
 
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0xA8F36 | Nemesis | An unfinished badnik named Bubbler's Mother. It would fly around the stage dropping particles on the floor that would turn into Bubblers. These also appear in the 2013 version via Debug Mode. In the August 21st build, code exists for Bubbler's Mother, which flies horizontally dropping sparkles that spawn object $55. According to concept art it was intended for "Chemical Factory Zone", which eventually became Chemical Plant Zone. |
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0xA9162 | Nemesis | The Bubbler dropped by Bubbler's Mother. It would stick to the floor for a bit before exploding into three bubbles. In the August 21st build, unfinished code exists for Bubbler, which is meant to occupy $55. According to concept art it was intended for "Chemical Factory Zone", which eventually became Chemical Plant Zone. |
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0xA9580 | Nemesis | In Crawl's sprites is what appears to be rocks or clumps of sand. Crawl was originally intended to pop out of the ground with the sand/rocks appearing under it. The idea was likely scrapped after Crawl was repurposed for Casino Night Zone. Interestingly the sprite is used in the August 21st build if Crawl's art is restored. The sand/rocks was also seen in the design sketch for Crawl. |
| Used | Intended |
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The BBat badnik uses palette 01, but it looks a bit odd. If it's set to use palette 00 (Sonic and Tails' palette), the ear and flame colors look a lot better. This wasn't fixed in any build of the game before its art and coding were removed from the ROM entirely.
Unused Objects
| Object ID | Graphic | Name | Description | ||||||
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| 4A |    |
Oct (Octus) | This badnik appears in Oil Ocean Zone in the final game, though its behavior is slightly different here:
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| 4D |   |
Stego (Stegway) | A triceratops-type badnik that appeared in a mockup screenshot of Hidden Palace Zone. It slowly moves back and forth, and when Sonic approaches it, it activates its thrusters and charges at Sonic like the snail badnik. It is placeable in Hidden Palace through Debug Mode, but its graphics are garbled without using PAR code 01C1D8:0007. | ||||||
| 4E |  |
Gator | A crocodile-type badnik, first seen in a mockup screenshot for Sand Shower Zone, though it's unclear whether this enemy was intended to appear there. It slowly moves back and forth, opening its jaws if it's facing Sonic and is within 64 pixels of him. It is placeable with debug in Hidden Palace Zone, but its graphics are garbled without using a PAR code. | ||||||
| 50, 51 |   |
Seahorse (Aquis) |
Object 50 (Seahorse):
Object 51 (Skyhorse):
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| 52 |   |
Billfish | A piranha-type badnik. It will move 32×(lower four bytes of subtype) pixels to the right before leaping, then jump in a high arc. Exactly how it works depends on its initial and current Y positions:
It is placeable with debug in Hidden Palace Zone, but its graphics are garbled without using a PAR code. | ||||||
| 79 |   |
Save (Lamppost) | This is the Sonic 1 lamppost with a very different design than the one seen in the final version of Sonic 2. It is placeable with Debug Mode in Emerald Hill Zone and Hill Top Zone. They appear in Green Hill Zone, but the graphics are garbled. |
Unused Subtypes
| Object Subtype | Graphic | Name | Description |
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| Monitors | |||
| 00 |  |
Static monitor | Does nothing when broken. In the final game (where it's also unused), this damages the player. |
| 03 |  |
Eggman monitor | Also does nothing in the proto and damages the player in the final, but this one is used in the final's 2-Player mode. |
| 08 |  |
Mystery monitor | Does nothing when broken...in this build. In the Simon Wai prototype, it activates Super Sonic's palette, with the rest of the attributes later being activated in the August 21st and Pre-Beta prototypes, before being replaced with the Teleport monitor in later builds. |
| 09 |  |
Spring monitor | Only present in this prototype and the Simon Wai build, but it does nothing when broken. Two guesses on how this would have worked:
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| Others | |||
| N/A | N/A | Chemical Plant Zone Platforms | The code in this version seems to be reused from object 52 in Sonic 1, which was used for the moving blocks in Marble, Labyrinth, and Scrap Brain Zones. Subtypes 02-03 (Marble Zone block that moves right when stepped on, then drops when it hits a solid tile), 04-07 (hidden block in Labyrinth Zone Act 1 activated by switch that leads to the quicker route), and 09-0A (sliding platforms in Scrap Brain Zone) are all unused in this build. |
| 00 | Boss | Chemical Plant Zone boss. The code was completely removed and the pointers to it are set to 0. Leftover symbol data call the subobjects "bossvac" and "vacumeguy". Its graphics do remain in the ROM, alongside leftover entries for loading them. However, the code was rediscovered in the August prototype, and can be ported over to the Nick Arcade prototype. With just some small object ID and pointer fixes and restoration of those graphics load entries, it'll work just about right out of the box, as shown in the video.
The behavior is different to the final, generally having slower movement. | |
Code Oddities
- Somehow, a compression from Kid Chameleon made it into the code, and is even used for Green Hill's chunks!
- The way the game decides the above is strange: When loading a level, the game checks if the Zone ID is specifically 02, 03, 04, or 05, and if not, it uses the Kid Chameleon decompression. Since Labyrinth Zone (ID 01) uses Chemical Plant's data, this does not match up, resulting in loading improper chunks.
- The routine to load animated stage tiles lists stages past all the way up to $0F, even though there are only $06 stages (including Sonic 1's ending); this seems the suggest the developers were already shifting the stage IDs around, which is further supported by the fact that Hidden Palace is listed as $08, which is its slot from the Simon Wai build onwards.
Object List/Source Code
A humongous object list can be found inside the ROM, along with some raw source code.
addsym nolist include "equ.lib" include "macro.lib" list xref colichgpat xref ringpat,itempat,butapat,kanipat,hachipat,togepat xref fishpat,fish2pat,mogurapat,shimapat2,jyamapat xref musipat,sjumppat,kamerepat,arumapat,kagebpat,ballpat xref firepat,fblockpat,signalpat,bobinpat,yoganpat,yogan2pat xref usapat,yadopat,boxpat,bryukapat,daipat,break2pat,yogancpat xref batpat,z5daipat,dai2pat,switch2pat,z4daipat xref elevpat,pedalpat,steppat,funpat,sisoopat,hassyapat xref brobopat,unipat,yaripat,udaipat,dai3pat,kazaripat,kassyapat xref awapat,mizupat,boupat,benpat,fetamapat,mawarupat,hagurumapat xref patapat,yukafpat,nokopat,dai4pat,doorpat,yukaepat,fire6pat xref elepat,yukaipat,scolipat,imopat,savepat,bigringpat,btenpat xref actionsub,actwkchk,frameout,playpat,dualmodesub xref flicpat,usagipat,pengpat,azarpat,fbutapat,niwapat,risupat xref kaitenpat,prodaipat,buranko0dpat xref frntlitpat,gempat,wfallpat,pltfrmpat xref takipat,banepat,dai00pat xref redzpat,bfishpat,seahorsepat,horsepat xref stegopat,wasppat,gatorpat,bbatpat,octpat,wfish2pat,snailpat xdef edit ;------------------------------------------------------------------------------ edit: moveq #0,d0 move.b editmode,d0 move.w edit_move_tbl(pc,d0.w),d1 jmp edit_move_tbl(pc,d1.w) edit_move_tbl: dc.w editinit-edit_move_tbl dc.w editmove-edit_move_tbl editinit: addq.b #word,editmode move.w scralim_up,editstack move.w scralim_n_down,editstack2 move.w #$0000,scralim_up move.w #$0720,scralim_n_down andi.w #$07ff,playerwk+yposi andi.w #$07ff,scra_v_posit andi.w #$03ff,scrb_v_posit move.b #0,patno(a0) move.b #0,mstno(a0) cmpi.b #spgamemd,gmmode bne.b .jump0 * move.b #7-1,stageno * move.w #$000,rotspd * move.w #$000,rotdir moveq #7-1,d0 bra.b .jump1 .jump0: moveq #0,d0 move.b stageno,d0 .jump1: lea edittbl,a2 add.w d0,d0 adda.w (a2,d0.w),a2 move.w (a2)+,d6 cmp.b editno,d6 bhi.b .jump move.b #0,editno .jump: bsr.w editpatchg move.b #12,edittimer move.b #1,edittimer+1 editmove: moveq #7-1,d0 cmpi.b #spgamemd,gmmode beq.b .jump moveq #0,d0 move.b stageno,d0 .jump: lea edittbl,a2 add.w d0,d0 adda.w (a2,d0.w),a2 move.w (a2)+,d6 bsr.w editwalk * bsr.w dirsprset jmp actionsub editwalk: moveq #0,d4 move.w #1,d1 move.b swdata1+1,d4 andi.w #$0f,d4 bne.b .jump0 move.b swdata1,d0 andi.w #$0f,d0 bne.b .jump move.b #12,edittimer move.b #$0f,edittimer+1 bra.w .lend .jump: subq.b #1,edittimer bne.b .jump1 move.b #1,edittimer addq.b #1,edittimer+1 * cmpi.b #255,edittimer+1 bne.b .jump0 move.b #255,edittimer+1 .jump0: move.b swdata1,d4 .jump1: moveq #0,d1 move.b edittimer+1,d1 addq.w #1,d1 swap d1 asr.l #4,d1 move.l yposi(a0),d2 move.l xposi(a0),d3 btst.l #0,d4 *swdata+0 beq.b .jump2 sub.l d1,d2 *yposi bcc.b .jump2 moveq #0,d2 .jump2: btst.l #1,d4 *swdata+0 beq.b .jump3 add.l d1,d2 *yposi cmpi.l #$7ff0000,d2 bcs.b .jump3 move.l #$7ff0000,d2 .jump3: btst.l #2,d4 *swdata+0 beq.b .jump4 sub.l d1,d3 *xposi bcc.b .jump4 moveq #0,d3 .jump4: btst.l #3,d4 *swdata+0 beq.b .jump5 add.l d1,d3 *xposi .jump5: move.l d2,yposi(a0) move.l d3,xposi(a0) .lend: btst.b #6,swdata1+0 beq.b .jump7 btst.b #5,swdata1+1 * c button check beq.b .jump77 subq.b #1,editno bcc.b .jump6 add.b d6,editno bra.b .jump6 .jump77: btst.b #6,swdata1+1 beq.b .jump7 addq.b #1,editno cmp.b editno,d6 bhi.b .jump6 move.b #0,editno .jump6: bra.w editpatchg .jump7: btst.b #5,swdata1+1 * c button check beq.b .jump8 jsr actwkchk bne.b .worknai ;z=0:ok z=1:no move.w xposi(a0),xposi(a1) move.w yposi(a0),yposi(a1) move.b patbase(a0),actno(a1) move.b actflg(a0),actflg(a1) move.b actflg(a0),cddat(a1) andi.b #$7f,cddat(a1) moveq #0,d0 move.b editno,d0 lsl.w #3,d0 move.b 4(a2,d0.w),userflag(a1) rts .worknai: .jump8: btst.b #4,swdata1+1 * b button check beq.b .jump9 moveq #0,d0 move.w d0,editmode move.l #playpat,playerwk+patbase move.w #$0780,playerwk+sproffset tst.w dualmode ; dual mode check beq.b .end move.w #$0780/2,playerwk+sproffset .end: move.b d0,playerwk+mstno move.w d0,xposi+2(a0) move.w d0,yposi+2(a0) move.w editstack,scralim_up move.w editstack2,scralim_n_down cmpi.b #spgamemd,gmmode bne.b .jump9 * clr.w rotdir * move.w #$040,rotspd * move.l #playpat,playerwk+patbase * move.w #$0780,playerwk+sproffset move.b #02,playerwk+mstno bset.b #cd_ball,playerwk+cddat bset.b #cd_jump,playerwk+cddat .jump9: rts editpatchg: moveq #0,d0 move.b editno,d0 lsl.w #3,d0 move.l 0(a2,d0.w),patbase(a0) move.w 6(a2,d0.w),sproffset(a0) move.b 5(a2,d0.w),patno(a0) * move.b 4(a2,d0.w),userflag(a0) bsr.w dualmodesub rts dcblw macro \1,\2,\3,\4,\5 dc.l (\1)*$1000000+(\2) dc.w (\4)+(\5)*$100 dc.w (\3) endm edittbl: dc.w edit1tbl-edittbl dc.w edit2tbl-edittbl dc.w edit3tbl-edittbl dc.w edit4tbl-edittbl dc.w edit5tbl-edittbl dc.w edit6tbl-edittbl dc.w edit7tbl-edittbl edit1tbl: dc.w 14 dcblw ring_act,ringpat,$26bc,0,$00 ;1: dcblw item_act,itempat,$0680,0,$00 ;2: dcblw kani_act,kanipat,$0400,0,$00 ;3: dcblw hachi_act,hachipat,$0444,0,$00 ;4: dcblw fish_act,fishpat,$0470,0,$00 ;5: dcblw toge_act,togepat,$04a0,0,$00 ;6: dcblw shima_act,shimapat2,$4000,0,$00 ;7: dcblw jyama_act,jyamapat,$66c0,0,$00 ;8: dcblw musi_act,musipat,$04e0,0,$00 ;9: dcblw sjump_act,sjumppat,$04a8,0,$00 ;10: dcblw kamere_act,kamerepat,$249b,0,$00 ;11: dcblw kageb_act,kagebpat,$434c,0,$00 ;12: dcblw save_act,savepat,$26bc,0,$01 ;13: dcblw colichg_act,colichgpat,$26bc,0,$00 ;14: edit2tbl: edit3tbl: ;zone0d dc.w 07 dcblw ring_act,ringpat,$26bc,0,$00 ;01: dcblw item_act,itempat,$0680,0,$00 ;02: dcblw sjump_act,sjumppat,$04a8,0,$00 ;03: dcblw colichg_act,colichgpat,$07bc,0,$00 ;04: dcblw kaiten_act,kaitenpat,$e000,0,$00 ;05: dcblw prodai_act,prodaipat,$e418,0,$00 ;06: dcblw buranko_act,buranko0dpat,$2418,0,$08 ;07: edit4tbl: ;zone00 dc.w 18 dcblw ring_act,ringpat,$26bc,0,$00 ;1: dcblw item_act,itempat,$0680,0,$00 ;2: dcblw save_act,savepat,$047c,0,$01 ;3: dcblw colichg_act,colichgpat,$26bc,0,$00 ;6: dcblw taki_act,takipat,$23ae,0,$00 ;7: dcblw taki_act,takipat,$23ae,3,$02 ;7: dcblw shima_act,dai00pat,$4000,0,$01 ;8: dcblw shima_act,dai00pat,$4000,1,$0a ;8: dcblw toge_act,togepat,$2434,0,$00 ;10: dcblw sisoo_act,sisoopat,$03ce,0,$00 ;9: dcblw sjump_act,banepat,$045c,0,$80 ;3: banev dcblw sjump_act,banepat,$0470,3,$90 ;3: baneh dcblw sjump_act,banepat,$045c,6,$a0 ;3: banevr dcblw sjump_act,banepat,$043c,7,$30 ;3: bane45 dcblw sjump_act,banepat,$043c,10,$40 ;3: bane45r dcblw wasp_act,wasppat,$03e6,0,$00 ;25 "" "" dcblw snail_act,snailpat,$0402,0,$00 ;25 "" "" dcblw wfish2_act,wfish2pat,$041c,0,$00 ;21 "" "" dcblw redz_act,redzpat,$0500,0,$00 ;20: will change dcblw bfish_act,bfishpat,$2530,0,$00 ;21 "" "" dcblw seahorse_act,horsepat,$2570,0,$00 ;22 "" "" dcblw skyhorse_act,horsepat,$2570,0,$00 ;23 "" "" dcblw stego_act,stegopat,$23c4,0,$00 ;24 "" "" dcblw wasp_act,wasppat,$032c,0,$00 ;25 "" "" dcblw gator_act,gatorpat,$2300,0,$00 ;26 "" "" dcblw bbat_act,bbatpat,$2350,0,$00 ;27 "" "" dcblw oct_act,octpat,$238a,0,$00 ;28 "" "" edit5tbl: edit6tbl: edit7tbl: ;zone08 dc.w 15 dcblw ring_act,ringpat,$26bc,0,$00 ;1: dcblw item_act,itempat,$0680,0,$00 ;2: dcblw bgspr_act,frntlitpat,$e485,3,$21 ;3: dcblw wfall_act,wfallpat,$e415,4,$04 ;4: dcblw break_act,pltfrmpat,$4475,0,$00 ;5: dcblw colichg_act,colichgpat,$26bc,0,$00 ;6: dcblw redz_act,redzpat,$0500,0,$00 ;20: will change dcblw bfish_act,bfishpat,$2530,0,$00 ;21 "" "" dcblw seahorse_act,horsepat,$2570,0,$00 ;22 "" "" dcblw skyhorse_act,horsepat,$2570,0,$00 ;23 "" "" dcblw stego_act,stegopat,$23c4,0,$00 ;24 "" "" dcblw wasp_act,wasppat,$032c,0,$00 ;25 "" "" dcblw gator_act,gatorpat,$2300,0,$00 ;26 "" "" dcblw bbat_act,bbatpat,$2350,0,$00 ;27 "" "" dcblw oct_act,octpat,$238a,0,$00 ;28 "" "" ;------------------------------------------------------------------------------ align ;------------------------------------------------------------------------------ end edit2tbl: dc.w 25 dcblw ring_act,ringpat,$26bc,0,$00 ;1: dcblw item_act,itempat,$0680,0,$00 ;2: dcblw sjump_act,sjumppat,$0523,0,$00 ;3: dcblw fish2_act,fish2pat,$2486,0,$08 ;4: dcblw mogura_act,mogurapat,$84a6,2,$00 ;5: dcblw yari_act,yaripat,$03cc,0,$00 ;6: dcblw yari_act,yaripat,$03cc,3,$02 ;7: dcblw box_act,boxpat,$43de,0,$00 ;8: dcblw switch2_act,switch2pat,$0513,0,$00 ;9: dcblw toge_act,togepat,$051b,0,$00 ;10: dcblw dai_act,udaipat,$43bc,0,$04 ;11: dcblw dai3_act,dai3pat,$43e6,0,$01 ;12: dcblw dai3_act,dai3pat,$43e6,1,$13 ;13: dcblw dai3_act,dai3pat,$43e6,0,$05 ;14: dcblw kazari_act,kazaripat,$443e,0,$00 ;15: dcblw dai3_act,dai3pat,$43e6,2,$27 ;16: dcblw dai3_act,dai3pat,$43e6,3,$30 ;17: dcblw kassya_act,kassyapat,$03f6,0,$7f ;18: dcblw uni_act,unipat,$0467,0,$00 ;19: dcblw awa_act,awapat,$8348,19,$84 ;20: dcblw mizu_act,mizupat,$c259,2,$02 ;21: dcblw mizu_act,mizupat,$c259,9,$09 ;22: dcblw bou_act,boupat,$43de,0,$00 ;23: dcblw ben_act,benpat,$4328,0,$02 ;24: dcblw save_act,savepat,$26bc,0,$01 ;25: * dcblw dai4_act,dai4pat,$41f0,4,$80 ;25: edit3tbl: dc.w 18 dcblw ring_act,ringpat,$26bc,0,$00 ;1: dcblw item_act,itempat,$0680,0,$00 ;2: dcblw hachi_act,hachipat,$0444,0,$00 ;3: dcblw toge_act,togepat,$051b,0,$00 ;4: dcblw sjump_act,sjumppat,$0523,0,$00 ;5: dcblw mfire_act,firepat,$0345,0,$00 ;6: dcblw fblock_act,fblockpat,$4000,0,$00 ;7: dcblw myogan_act,yoganpat,$63a8,0,$00 ;8: dcblw yogan2_act,yogan2pat,$63a8,0,$00 ;9: dcblw box_act,boxpat,$42b8,0,$00 ;10: dcblw yado_act,yadopat,$247b,0,$00 ;11: dcblw bryuka_act,bryukapat,$42b8,0,$00 ;12: dcblw dai_act,daipat,$02b8,0,$00 ;13: dcblw break2_act,break2pat,$62b8,0,$00 ;14: dcblw yoganc_act,yogancpat,$8680,0,$00 ;15: dcblw bat_act,batpat,$04b8,0,$00 ;16: dcblw imo_act,imopat,$24ff,0,$00 ;17: dcblw save_act,savepat,$26bc,0,$01 ;18: edit4tbl: dc.w 15 dcblw ring_act,ringpat,$26bc,0,$00 ;1: dcblw item_act,itempat,$0680,0,$00 ;2: dcblw elev_act,elevpat,$4000,0,$00 ;3: dcblw break2_act,break2pat,$44e0,2,$00 ;4: dcblw shima_act,z4daipat,$4000,0,$00 ;5: dcblw pedal_act,pedalpat,$4000,0,$00 ;6: dcblw step_act,steppat,$4000,0,$00 ;7: dcblw fun_act,funpat,$43a0,0,$00 ;8: dcblw sisoo_act,sisoopat,$0374,0,$00 ;9: dcblw sjump_act,sjumppat,$0523,0,$00 ;10: dcblw mfire_act,firepat,$0480,0,$00 ;11: dcblw bgspr_act,hassyapat,$44d8,0,$00 ;12: dcblw brobo_act,brobopat,$0400,0,$00 ;13: dcblw uni_act,unipat,$2429,0,$00 ;14: dcblw save_act,savepat,$26bc,0,$01 ;15: edit5tbl: dc.w 15 dcblw ring_act,ringpat,$26bc,0,$00 ;1: dcblw item_act,itempat,$0680,0,$00 ;2: dcblw toge_act,togepat,$051b,0,$00 ;3: dcblw sjump_act,sjumppat,$0523,0,$00 ;4: dcblw aruma_act,arumapat,$04b8,0,$00 ;5: dcblw signal_act,signalpat,$0000,0,$00 ;6: dcblw bobin_act,bobinpat,$0380,0,$00 ;7: dcblw kani_act,kanipat,$0400,0,$00 ;8: dcblw hachi_act,hachipat,$0444,0,$00 ;9: dcblw yado_act,yadopat,$247b,0,$00 ;10: dcblw shima_act,z5daipat,$4000,0,$00 ;11: dcblw dai2_act,dai2pat,$4000,0,$00 ;12: dcblw switch2_act,switch2pat,$0513,0,$00 ;13: dcblw imo_act,imopat,$24ff,0,$00 ;14: dcblw save_act,savepat,$26bc,0,$01 ;15: edit6tbl: dc.w 29 dcblw ring_act,ringpat,$26bc,0,$00 ;1: dcblw item_act,itempat,$0680,0,$00 ;2: dcblw brobo_act,brobopat,$0400,0,$00 ;3: dcblw uni_act,unipat,$0429,0,$00 ;4: dcblw imo_act,imopat,$22b0,0,$00 ;5: dcblw buranko_act,fetamapat,$4391,2,$07 ;6: dcblw haguruma_act,hagurumapat,$c344,00,$e0 ;7: dcblw dai_act,daipat,$22c0,2,$28 ;8: dcblw switch2_act,switch2pat,$0513,0,$00 ;9: dcblw pata_act,patapat,$4492,0,$03 ;10: dcblw pata_act,yukafpat,$04df,0,$83 ;11: dcblw noko_act,nokopat,$43b5,0,$02 ;12: dcblw break2_act,break2pat,$43f5,0,$00 ;13: dcblw dai_act,daipat,$4460,3,$39 ;14: dcblw dai4_act,dai4pat,$22c0,0,$00 ;15: dcblw door_act,doorpat,$42e8,0,$00 ;16: dcblw dai4_act,dai4pat,$22c0,1,$13 ;17: dcblw noko_act,nokopat,$43b5,0,$01 ;18: dcblw dai4_act,dai4pat,$22c0,1,$24 ;19: dcblw noko_act,nokopat,$43b5,2,$04 ;20: dcblw dai4_act,dai4pat,$22c0,1,$34 ;21: dcblw yukae_act,yukaepat,$44c3,0,$00 ;22: dcblw fire6_act,fire6pat,$83d9,0,$64 ;23: dcblw fire6_act,fire6pat,$83d9,11,$64 ;24: dcblw ele_act,elepat,$047e,0,$04 ;25: dcblw yukai_act,yukaipat,$42f0,0,$00 ;26: dcblw scoli_act,scolipat,$8680,0,$11 ;27: dcblw buta_act,butapat,$2302,0,$04 ;28: dcblw save_act,savepat,$26bc,0,$01 ;29: * dcblw ring_act,playpat,$0780,50,$00 ;28: * dcblw usa_act,usapat,$0448,0,$00 ;5: * dcblw mawaru_act,mawarupat,$4348,16,$00 ;7: edit7tbl: dc.w 02 *13 dcblw ring_act,ringpat,$26bc,0,$00 ;1: dcblw ring_act,ringpat,$26bc,8,$00 ;2: * dcblw bobin_act,bobinpat,$0380,0,$00 ;2: * dcblw usagi_act,flicpat,$05a0,0,$0a ;3 * dcblw usagi_act,flicpat,$05a0,0,$0b ;4 * dcblw usagi_act,flicpat,$05a0,0,$0c ;5 * dcblw usagi_act,usagipat,$0553,0,$0d ;6 * dcblw usagi_act,usagipat,$0553,0,$0e ;7 * dcblw usagi_act,pengpat,$0573,0,$0f ;8 * dcblw usagi_act,pengpat,$0573,0,$10 ;9 * dcblw usagi_act,azarpat,$0585,0,$11 ;10 * dcblw usagi_act,fbutapat,$0593,0,$12 ;11 * dcblw usagi_act,niwapat,$0565,0,$13 ;12 * dcblw usagi_act,risupat,$05b3,0,$14 ;13
Something interesting to notice is this group of code:
dcblw redz_act,redzpat,$0500,0,$00 ;20: will change dcblw bfish_act,bfishpat,$2530,0,$00 ;21 "" "" dcblw seahorse_act,horsepat,$2570,0,$00 ;22 "" "" dcblw skyhorse_act,horsepat,$2570,0,$00 ;23 "" "" dcblw stego_act,stegopat,$23c4,0,$00 ;24 "" "" dcblw wasp_act,wasppat,$032c,0,$00 ;25 "" "" dcblw gator_act,gatorpat,$2300,0,$00 ;26 "" "" dcblw bbat_act,bbatpat,$2350,0,$00 ;27 "" "" dcblw oct_act,octpat,$238a,0,$00 ;28 "" ""
These lines of code are in the block that makes up Hidden Palace Zone's debug list from an earlier build. The content in the list appears to be identical to the actual compiled version in the ROM; however, it does give us information on the objects in the Zone that may have been previously unknown:
- Redz is the red T-rex badnik that appears in Hidden Palace.
- Bfish is the jumping fish badnik that was unused by the Simon Wai prototype.
- Seahorse is Aquis, the seahorse badnik that was in the final game in Oil Ocean Zone.
- Skyhorse is the second Aquis object in Hidden Palace's debug list (the version that shoots a harmless projectile).
- Stego is the triceratops badnik that was unused by the Simon Wai prototype.
- Wasp is Buzzer, the bee badnik that's in Emerald Hill Zone in all known versions of Sonic 2. In this prototype, it also has a home in Hidden Palace's debug list.
- Gator is the alligator/crocodile badnik that is unused by the Simon Wai prototype.
- Bbat is the dive-bombing bat that appears in Hidden Palace Zone.
- Oct is Octus, the octopus badnik that was in the final game in Oil Ocean Zone.
These same lines are duplicated in the debug list for Emerald Hill, but unused because the game is told that Emerald Hill's debug list will have 18 entries, and the Hidden Palace enemies are all after entry number 18.
This chunk of uncompiled code also indicates that the Zone order present in this build was going to be changed even at this early stage. Emerald Hill's debug list is labeled as Zone 00, which is Green Hill in this build but Emerald Hill in later builds. Similarly, Hidden Palace is labeled as Zone 08, which is where it resides in later builds and the final.
The second set of editXtbl labels seems to correspond with the debug lists of Sonic 1, but doesn't exactly match any extant build. Notably, the edit2tbl and edit6tbl lists have entries prefixed by asterisks, which don't seem to appear in the final game. The asterisked entries in edit7tbl exist in Sonic 1 REV00 only.
Misc. Leftovers/Earlier Versions of Objects
| To do: Get some more objects documented here, if there are any. |
Inside the ROM, mixed in with the symbol tables and debug mode source code is what appears to be leftover RAM contents from the assembler that includes additional symbols, and also assembled code. What should be noted is that the data is from a previous build (CES) , and some objects do indeed have different code.
Emerald Hill Zone Boss
Differences include only 2 hit points, different positioning, a lack of hitbox for the drill, and a weird bobbing movement for the ship's body. The wheels also do not detect floor collision until they fall off the body.
"Overdump" Data Leftovers
The Nick Arcade build contains leftover data from ToeJam & Earl starting at 0xE1670 until the end of the ROM, however this "overdump" contains no differences from final. Additional information on overdump content can be found here.
