Sonic the Hedgehog 3

Sonic the Hedgehog 3/es
También conocido como: Baramdori Sonic 3 (KR) Desarrolladores: Sonic Team, Sega Technical Institute Publicados: Sega (JP/EE.UU/EU), Samsung (KR), Tec Toy (BR) Plataforma: Genesis A la venta en Japón: May 27, 1994 A la venta en los EE.UU.: February 2, 1994 A la venta en Europa: February 24, 1994 A la venta en Corea: 1994 A la venta en Brasil: 1994 Este juego tiene áreas sin uso. Este juego contiene personajes jugables no usados. Este juego tiene código sin usar. Este juego tiene enemigos no usados. Este juego tiene gráficos sin usar. Este juego tiene habilidades no usadas. Este juego tiene música sin usar. Este juego tiene sonidos sin usar. Este juego contiene material de depuración. Este juego tiene una prueba de audio sin usar. Este juego tiene un selector de nivel oculto. Este juego tiene diferencias entre versiones regionales.

Sonic 3 es el tercer juego de la trilogía Sonic de 16 bits y el primer juego con el equidna rojo, Knuckles. Originalmente un gran juego, Sonic 3 se dividió en dos juegos debido a limitaciones de tiempo y costos de cartuchos; la segunda mitad de la historia es su secuela directa, Sonic & Knuckles.

Subpáginas

Selección de Nivel/Modo de Depuración

Para acceder al la selección de nivel y modo debug, pulsa Arriba, Arriba, Abajo, Abajo, Arriba, Arriba, Arriba, Arriba después de que la pantalla del logotipo de SEGA se apague y Sonic comience a moverse, pero antes de que aparezca la pantalla de título (aproximadamente 4.31 segundos después del arranque). Solo se tiene aproximadamente 1.3 segundos para ingresar, y debido a que esta pantalla tiene un número absolutamente ridículo de marcos de retraso, puede que no siempre funcione; escucharás el sonido de la recolección de Rings si lo hiciste bien. Alternativamente, puedes desbloquear el nivel seleccionado por estos métodos alternativos:

• Se puede acceder al menú sobrante de Sonic 2 (ver más abajo) e ingresar el código de selección de nivel de Sonic 2 en la prueba de sonido (19, 65, 09, 17).
• También puedes usar el código de Game Genie AA6T-AAXC para acceder al nivel de selección.
• Si juegas en una consola Mega Drive / Genesis real y no te importa arriesgar la seguridad a largo plazo de tu consola y tus cartuchos, entonces otro método es cargar Sonic 2, desbloquear su nivel de selección (19, 65, 09, 17 en la prueba de sonido), cambiar el cartucho con Sonic 3 sin apagarlo y luego presionar Reset. Esto funciona porque la variable RAM que desbloquea la selección de nivel se conserva cuando se restablece la consola (Sonic 3 se creó con el código fuente de Sonic 2 y, por lo tanto, comparte varias variables de RAM.).

Selección de Niveles

Para encontrar la selección de en la pantalla de título, simplemente presione Arriba para revelar "SOUND TEST" y presione Start. Para activar el modo de depuración, seleccione un archivo/nivel, mantenga presionado A y presione Start y mantenga presionado A hasta que comience el nivel. También puede mantener presionado el botón C y presiona Start para resaltar los mosaicos de fondo de alta prioridad (los mosaicos que se superponen a Sonic y otros sprites).

Modo de Depuración

Mientras está en modo de depuración, tiene acceso a lo siguiente:

• Invencibilidad
• Tiempo infinito
• Coordenadas de depuración (en lugar de puntuación)
• Contador de Sprite (en lugar de tiempo)
• Modo de colocación: presione B para ingresar al modo de colocación, lo que le permite mover Sonic a cualquier lugar del nivel con el D-Pad y colocar objetos de una lista predefinida (no todos los objetos pueden estar disponibles en un nivel determinado) En este modo:
  • Presione A para avanzar un objeto.
  • Mantenga presionado A y presione C para retroceder un objeto.
  • Presione C para colocar el objeto.
  • Presione B nuevamente para volver al modo de juego normal.
• Visor de animación de personajes: mantenga presionado C y presione B para recorrer rápidamente todos los marcos de animación disponibles para el personaje actual (pause el juego y use el avance de fotogramas para ver fotogramas individuales). Presione B nuevamente para volver al modo de juego normal.
• Opciones de pausa:
  • Presione A para volver a la selección de nivel
  • Mantén presionado B para avanzar el juego en cámara lenta.
  • Presione C para avanzar un cuadro.

Si mueres, presiona B para ingresar al modo de colocación, y luego presiona B en un lugar seguro para revivirte. Sin embargo, tratar de colocar un objeto en este estado de muerte congelará el juego. Además, no ingrese al modo de depuración en ningún punto donde el sprite de Sonic gire (por ejemplo, mientras está de pie sobre los cilindros rojo y blanco en Carnival Night Zone) o el juego se bloqueará.

Secretos

El menú de selección de nivel muestra cual era el orden de nivel en un principio. Las zonas de "Sonic 3" están en su orden normal, pero Flying Battery de "Sonic & Knuckles" esta listado entre Carnival Night y Ice Cap. Después de Launch Base está Mushroom Valley (nombre temprano para Mushroom Hill) y Sandopolis, pero ninguno de estos pueden ser seleccionados.

Según los comentarios de la guía de estrategia de "Sonic Jam", Ice Cap debía seguir después de Flying Battery ya que se suponía que Sonic debía romper la puerta al final de la zona y usarla como tabla de snowboard. También hay una variedad de canciones sin usar, todas de "Sonic & Knuckles", en la prueba de sonido.

Además, todos los gráficos (incluidos los iconos de nivel) son reciclados de Sonic the Hedgehog 2, y los iconos se muestran en el orden de "Sonic 2", como el icono de Emerald Hill para Angel Island y el icono de Casino Night para Carnival Night. Curiosamente, la segunda entrada de "2P VS" muestra el icono no utilizado de Hidden Palace.

==Zona sin usar== El ID de zona $0D no está en uso, pero parece estar vacío. Intenta cargar algunos recursos de los créditos finales. El Acto 2 de esta Zona se usó más tarde para los créditos de Sonic 3 & Knuckles. Intentar cargar esta zona generalmente bloqueará el juego, y si logras salir de ella, causará algunos errores muy extraños que harán que el juego actúe de manera muy extraña.

Se cree que esta zona originalmente estaba destinada a ser una zona 2P VS por varias razones: * Está internamente al lado de todas las zonas 2P utilizadas. * En el prototipo del 3 de noviembre y el puerto de Windows, hay una pista sin usar (a menudo denominada incorrectamente tema de Super Sonic sin usar) que podría ubicarse para una zona 2P. * Hay seis zonas 2P enumeradas en la selección de nivel. Sin embargo, la lista de la sexta zona simplemente apunta a la etapa de bonificación de Gumball Machine.

Restos del menú de "Sonic 2"

Al configurar el modo de pantalla del juego en $24, puede acceder al menú de opciones de "Sonic 2" en "Sonic 3". Alternativamente, puede usar el código de parche FFF600:2400 o hackear el menú usted mismo.

Como todas las opciones aquí son seleccionables normalmente a través de otros métodos en "Sonic 3", el único beneficio real de esto es ingresar el código de selección de nivel de "Sonic 2" para acceder a él en "Sonic 3".

También es posible encontrar el selector de niveles para 2 jugadores de "Sonic 2" usando el código de parche FFF600:1C00. Sin embargo, al seleccionar cualquiera de las zonas en esta pantalla lo enviará de regreso a la pantalla de título, por lo que no puede hacer nada con este menú.

Leftover graphics from the Results Menu can be found.

Octava etapa especial

Hay un octavo escenario especial con una Chaos Emerald gris (muy parecida a la quinta Emerald) que es inaccesible durante el juego normal. Para acceder a él, abra la selección de nivel, establezca la selección de prueba de sonido en 07, luego mantenga presionada A y presione Iniciar en "Etapa especial 2".

El escenario es completamente jugable, aunque ocasionalmente puede ralentizarse al recoger una esfera azul, lo que puede haber contribuido a su eliminación. La Esmeralda no tiene ningún efecto especial en el juego y no aparece en la cuenta final de la etapa de ninguna forma que no sea un aumento de puntuación. La falta total de anillos también hace que sea imposible obtener una bonificación perfecta en esta etapa.

"Sonic Mania reutilizaría este diseño para un escenario de bonificación, reemplazando algunas de las esferas azules con anillos para permitir una bonificación perfecta.

(Source: Sonic Retro)

==Niveles de agua en la zona base de lanzamiento Acto 1== Hay 5 áreas que contienen agua en la zona base de lanzamiento Acto 1 que elevan o reducen el nivel del agua en algunas áreas específicas. A partir de esto, no es irrazonable suponer que ambos actos de LBZ contendrían agua.

Para ver estos niveles, agregue el código de parche FFF730:0100' y cambie VDP 0x04 a 0x14. Los niveles de agua se pueden ver en la ROM en la dirección 0x5350.

El primer nivel se puede ver en la dirección ROM en 0x51EE y debería aumentar el nivel del agua a 0A80, pero no lo hace debido a un error.

El segundo nivel se ubica desde 0000 hasta 0E00 y eleva el nivel del agua hasta 0B00.

El tercer nivel se ubica desde 0E00 hasta 2340 y sube el agua hasta 0A00

El cuarto nivel se ubica desde 2340 hasta 2C00 y baja el nivel del agua hasta 0AC8.

El quinto nivel se ubica desde 0AC8 hasta FFFF y hace desaparecer el agua.

==Hydrocity Dominós==
 Estos mosaicos con forma de dominó/dado se usan como gráficos de marcador de posición para los orbes animados en las columnas de fondo de Hydrocity.  Se pueden ver en el juego si se evita que los gráficos animados se carguen de alguna manera:
 

==Objetos no utilizados== ===Esferas rojas giratorias===

Una masa giratoria de esferas rojas, que puede ser colocado en la primera mitad del Acto 1 de Angel Island a través del modo de depuración. Las esferas se parecen a las que aparecen en las etapas especiales del juego, pero el objeto en sí parece no tener ningún propósito aparente en el juego. Cuando se coloca, se producen muchas complicaciones de paleta y VRAM en el nivel, y el juego se ralentiza considerablemente. El objeto se puede manipular con el segundo controlador.

• Arriba - Gira el objeto verticalmente. * Derecha - Gira el objeto horizontalmente. * Abajo/Izquierda - Mueve el objeto hacia arriba o hacia abajo. * A/C - Cambia el tamaño del objeto. * B - Gira el objeto hacia los lados. * Inicio - Alterna la rotación automática.

El prototipo del 3 de noviembre de 1993 revela, sin embargo, que son restos de una demostración técnica que sirvió para probar la mecánica 3D de las etapas especiales. Vale la pena señalar que el objeto no es idéntico al visto en la etapa de prueba.

Sprite de árbol en primer plano sin usar

A pesar de su apariencia similar a los árboles que se ven al final del Acto 2 de Angel Island Zone cuando Robotnik vuela por el bosque, este es en realidad un objeto completamente separado que no se usa por completo. Está destinado a colocarse en primer plano, y sus gráficos están ubicados con los gráficos de interruptor no utilizados, lo que sugiere que puede haber sido utilizado anteriormente en el desarrollo. Se puede colocar con el modo de depuración.

Muro Rompible

Una pared rompible, que se puede colocar en Angel Island Act 2 usando el modo de depuración. Viene en dos variaciones: una que actúa como un obstáculo de pared que se puede destruir con el Spin Dash y otra que actúa como una puerta que se abre con un interruptor.

Botón Noche de Carnaval

Un botón de propósito desconocido. Se puede colocar en Act o Carnival Night Zone a través del modo de depuración, pero no parece hacer nada. Tampoco se usa en Sonic 3 & Knuckles. Knuckles (la historia de Sonic/Tails) presiona un botón como ese en el Acto 2 para oscurecer el lugar.

Objeto de anillo de noche de carnaval

Un objeto desconocido que parece generar una colisión de pendiente cuando se coloca.

Bloque Rompible IceCap

Un bloque brillante que se puede colocar en Act o en IceCap Zone a través del modo de depuración. Saltar sobre él lo destruye como los bloques de hielo. Tampoco se usa en Sonic 3 & Knuckles.

Modo Competición Picos

Un conjunto de picos para el modo Competición. Los picos no aparecen en ninguno de los cinco cursos, pero se pueden colocar con el modo de depuración.

Ascensor sin usar

Un objeto de ascensor no utilizado definido como ID de objeto 12. Los gráficos ya no existen, pero el nombre del símbolo sobrante de elev06 en Sonic & Knuckles Collection parece indicar que estaba destinado a Launch Base Zone, posiblemente antes de que se crearan los nuevos ascensores. Se puede operar mediante un interruptor.

Plataforma giratoria

Una especie de objeto similar a una plataforma giratoria con gráficos indefinidos, con ID de objeto 1A. Cuando se toca, bloquea al jugador en el centro del objeto; cuanto más rápido corre el jugador, más lejos son lanzados después de salir. Sin embargo, es probable que este comportamiento sea un efecto secundario no deseado de un error en el código del objeto. Si se corrige el error, se comporta de forma más lógica como un obstáculo giratorio estándar. La rotación del objeto se puede manipular usando el segundo controlador. Fue etiquetado como "rollita" en los datos de símbolos de Sonic & Knuckles Collection. Es posible que este objeto también se haya creado para Launch Base Zone.

Estructura giratoria

Un objeto curioso que daña al jugador si se golpea desde arriba, pero se balancea de lado a lado si se golpea desde abajo. No se han encontrado sus gráficos y su animación se parece a algo que gira. Identificado como Objeto 1C. También puede haber sido creado para Launch Base Zone.

Plataforma grabable

Una plataforma normal con un fondo agarrable. La parte inferior de los gráficos está dañada, pero parece encajar mejor en Launch Base Zone. Su ID es 1D.

Objeto de daño de lava sobrante

Este objeto se usó en "Sonic 1" y "Sonic 2" para dañar al jugador cuando toca la lava, pero no funciona aquí. Es posible cambiar el tamaño del área modificando su variable. ID 27.

Primavera arriba y abajo

Diseñado para Flying Battery Zone, este objeto crea un resorte que sube y baja temporalmente. También hace rebotar al jugador anormalmente alto. Identificado como ID 3D.

Gran Sonic en la pantalla de Sega (Sonic 2)

Hay código sobrante del gran Sonic en la pantalla de Sega en Sonic 2. El objeto parece ser un remanente bastante antiguo, ya que todavía usa el antiguo formato de objeto Sonic 2. Las asignaciones de sprites todavía existen.

Objeto Escudo

El código para un cuarto tipo de escudo existe dentro de la ROM. El escudo en sí es el escudo ordinario no elemental como se ve en Sonic 1 y Sonic 2. Se desconoce si esto es simplemente un sobrante o si fue planeado originalmente para el juego. Vale la pena señalar que el sonido del escudo de Sonic 2 no se usa en la prueba de sonido. Curiosamente, existe bajo tres subtipos de escudo de monitor válidos: 00, 02 y 03.

Puede activar este tipo de escudo manualmente cambiando la dirección de RAM FFB02B:00 a 01.

Otros objetos no utilizados

To do: * Agregue los otros objetos que se identificaron en el Prototipo del 3 de noviembre

Los objetos 8F-98 se borran solos cuando se cargan, lo cual es bastante inusual. Uno de estos objetos se usa en el diseño de objetos de Mushroom Valley, lo que sugiere que alguna vez fueron objetos que pertenecieron a las Zonas Sonic & Knuckles. Los objetos 6F-7F se representan como anillos en "Sonic 3" y aparentemente se eliminaron manualmente, pero en "Sonic 3C" (prototipo 0408), estas identificaciones pertenecen a objetos de Flying Battery Zone. El objeto 84 es otro objeto sin usar y eliminado; según el Prototipo del 3 de noviembre, este objeto era una versión temprana de Hey Ho, el jefe del Acto 1 de Mushroom Valley/Hill.

Datos de mapeo S&K no utilizados

En Sonic 3 quedan algunos datos de asignación de sprites sobrantes para los objetos de Sonic & Knuckles, que consisten principalmente en badniks que habrían aparecido en las zonas de Sonic & Knuckles.

Introducción de tabla de surf sin usar

Sprites para una secuencia de introducción alternativa en la que Sonic navega hacia Angel Island, en lugar de montarse en el Tornado. Curiosamente, Sonic se parece a su encarnación de Sonic 2, lo que lo convierte en un remanente bastante antiguo. Esta introducción se utiliza en el prototipo del 3 de noviembre de 1993. En la final, el sprite de Sonic surf todavía se puede colocar en la Zona 1 de Angel Island a través del modo de depuración.

Los sprites usados ​​cuando Sonic se deshace de la tabla de surf.

Unused Sprites

Sprite	Description
	An item monitor displaying static that harms you when broken, change a monitor to subtype 00 to view the static monitor. Used in Angel Island in the November 3rd prototype.
	A monitor that can transform Sonic into Super Sonic and Tails into Glitched "Super Tails" without needing to collect Chaos Emeralds. This monitor is present in Debug mode only.
	Sonic in his signature "waiting" pose, but instead of pointing towards the direction he's facing, he falls asleep from boredom. Interestingly, this animation was used in the Game.com version of Sonic Jam, Sonic Classic Collection and Sonic X for the Leapster.
	Sonic whistling. This was also used in the Game.com Sonic Jam.
	A black & white version of Sonic's death sprite, similar to the one seen in the previous two games. It's still not used.
	This would be used for Flying Battery Zone's monkey bars in Sonic & Knuckles and Tails' sprites will be used in Sonic 3 and Knuckles. Sonic's sprites seem to match up better with his Sonic 2 sprites than his Sonic 3 ones, which wasn't fixed in Sonic & Knuckles.
	This would be used for the intro cutscene of Mushroom Hill Zone Act 2 in Sonic & Knuckles.
	This would be used in Sonic & Knuckles when grabbing the swinging poles in Mushroom Hill Zone.
	This would be used in Sandopolis Zone in Sonic & Knuckles when scaling down the towers.
	Leftover continue icons from Sonic 2. These are still mapped to the original palette.
	A leftover animation from the Sonic 2 continue screen.
	Knuckles' life icon which would later see use in Sonic & Knuckles.
	Knuckles text which would have been used upon Act and Special Stage completion. It can be seen in-game by making a save file with Knuckles as your character.
	Unused Knuckles sprite for the continue screen.
	Unused Knuckles sprite from the data select screen. It was later used in Sonic 3 & Knuckles. It can be seen via the way listed above.
	Unused gliding, climbing and falling frames for Knuckles in 2-Player mode, despite him not having these abilities there (he uses Sonic's Insta-Shield ability, much like his single-player "slot" uses Sonic). The recombined game, Sonic 3 & Knuckles, does not restore these functions (assuming they were ever implemented).
	A set of sprites where Eggman has a panicked facial expression. One of these sprites shows him attempting to jump. Sonic & Knuckles didn't use them either.
	This was used for the Flying Battery laser boss. It was later used in Sonic & Knuckles.
	Appears to be nothing more than Eggman flying away towards the horizon. This is actually another object with coding left in the game, but it's never called by any routine. The animation somewhat fits with the way the Death Egg falls at the ending cutscene after the Big Arms fight and would've teased the second part of the game, however, the Death Egg noticeably falls on the opposite direction of where Eggman goes in the actual game, it was probably originally meant to be falling from the left side instead. This can be re-enabled using the PAR code 05165A:04F2.
	Dr. Robotnik poses intended for the unused Flying Battery Zone Act 2 boss and would later appear in the lock-on game, however, the left-most sprite also goes unused even during the actual boss fight due to a coding error, and it was meant to appear when the Hang Mobile started swinging up and down, this was not fixed in Sonic & Knuckles.
	A smaller rendition of the Death Egg that seems to be part of a Death Egg hologram projector, which itself is unused in Sonic & Knuckles.
	Diagonal frames of the Penguinator badnik from IceCap Zone. These can be seen for a split-second if you place a Penguinator on the large hill at the beginning of Act 1 using debug mode.
	A save file icon for Flying Battery Zone before it was re-ordered to be in Sonic & Knuckles, which is different than the corresponding icon in Sonic 3 & Knuckles, displaying the interior part of the stage rather than the exterior. It resembles a part of the beginning section of the zone from the November 3rd Prototype. You can view this icon in the PC and Genesis versions by hacking the save data to access level slot $04, or by using PAR codes 00C324:601E + 00C338:6002 to view it in a completed game save slot while scrolling through the zones. (Source: Sonic Retro)
	Unused sprites from IceCap Zone Act 1. While the teleporter pad ended up being used in Sonic 3 & Knuckles for Knuckles' transition into the stage, the unusually oversized ice boulder which actually fits in some of the cave's halls was never used.
	An unused S gumball intended for the Gumball Machine bonus stage. It can also be seen hidden among the other balls at the bottom of the machine. Its programming is undefined, though a possibly useless ID of 08 might have been created for this gumball, if the S and the palette cycle which is nearly the same one used on Super Sonic is any indication, it might have been related to it. It's also unused in Sonic & Knuckles. It does, however, set an unrelated RAM address to 07.
	Located far in the back of the gumball machine, obscured by the other gumballs and the glare of the glass, sits a blue gumball. The shade of blue seen here varies from the bubble shield gumball.
	A sprite resembling a metallic structure that, based on its location at offset 18DB46, would have been used during the fight against Robotnik in Angel Island Zone Act 2. The assembly and color palettes may be wrong.
	Leftover sprites from early versions of the game that had a progress bar in Competition mode. These sprites can be seen in the Nov 3, 1993 prototype.
	Unused lap counter digits. These sprites can be seen in the Nov 3, 1993 prototype, as the lap number has no cap, but they use an older style.
	This is an unused font, located directly after the font for the timer in the competition mode. It's very likely that it was used earlier in development.
	This graphic that looks vaguely like a clock or medal, was located in the data for the font above. The palette is unknown.
	A set of sprites resembling a shadow found within the graphics used for the Tornado. It would have likely appeared under the Tornado during the opening intro.
	During the boss fight at the end of Marble Garden Act 2, Robotnik will fly towards the horizon before initiating his next attack. This effect uses a sprite software scaling algorithm that allows this to be achieved. However, the effect begins taking place before Robotnik flies completely onscreen and as a result, the full unscaled sprite is never seen.
	These sprites are used in Knuckles' unused Marble Garden Act 2 boss battle.
	This sprite is used in the Launch Base Zone Act 2 laser boss battle, but it is obscured and cannot be seen.
	While these graphics are used in Sonic & Knuckles, they appear in this game in a mangled form on Knuckles' unused, broken post-Launch Base Zone Act 2 boss cutscene.
	These do appear in mangled form in Knuckles' unused, broken post-Launch Base Zone Act 2 boss cutscene. These graphics were later used in three Sonic 3 limited edition/Sonic & Knuckles prototypes; Sonic 3C 0408, Sonic 3C 0517, and Sonic & Knuckles 0525 respectively. This was a bomb shoot that Eggrobo used to drop the bomb on Knuckles. Oddly, it is not used in the final game, but it might have something to do with Big Arm's graphics loading over the graphics of the bomb shoot (Knuckles originally did not fight Big Arms).
	The Blaster badnik from Flying Battery Zone still has its sprites and object code leftover in Sonic 3. The palette used here is from IceCap Zone because Flying Battery's true palette no longer exists.
	The Technosqueek badnik from Flying Battery Zone also has its sprites and object code leftover in Sonic 3.
	Owing to its late removal, many assets related to Flying Battery's bosses are still in the ROM, but unused. This is used for the Gapsule miniboss in Sonic & Knuckles, but with minor palette differences. The boss itself still exists and can be fought by hacking the game to load Flying Battery Zone Act 1.
	The laser turret in Flying Battery Zone Act 2's mid-boss, the laser barriers on either side of the arena and Eggman's control panel all still exist and are fully functional, later appeared in Sonic & Knuckles, of course...
	The Hang Mobile is here too.
	This light bulb is used in Carnival Night Zone, but it has an unused function; if the water rises over it, it will explode and show the unused frame seen on the right. This can never be seen because the light bulbs never make contact with the water in the actual game.
	Palette and graphics data for the gold player-bouncing spheres that are present in the Sonic & Knuckles special stages exist in Sonic 3. The palette is loaded every time the player enters the special stage, but none of these spheres ever appear, their coding is also non-existent in the game.

Unused Competition Mode Title Cards

Unused title cards exist for Competition Mode and are fully programmed, but disabled. They can be re-enabled using the following patch codes:

Code	Description
02CA90:6030	Enable 2P zone title cards
02CACA:FE10	Pick title card by Current_zone
02CB42:004D	Set art_tile instead of render_flags
02CB44:000B	Set art_tile instead of render_flags

When the title cards are enabled, VRAM issues with the level graphics occur, which may have contributed to their removal. Interestingly, the title cards are still using the old level order where Desert Palace Zone precedes Chrome Gadget Zone. This was changed in the final so that the zone names used alphabetical order.

Unused Super Sonic Frame

In-game	Intended

Super Sonic has an extra idle frame and extra colors in his palette cycle that end up going unused. The unused frame makes the animation a bit smoother than what is actually seen. The unused colors are due to an oversight in one line of code, it mistakenly skips the last six frames ($36 instead of $3C).

Oddly, the smoother colors don't happen with underwater palettes, suggesting it was scrapped early.

(Source: Sonic 3 Unlocked)

Green Bomber

While not technically unused, only the bottom of the ship appears in normal gameplay.

Act Clear Signs

Early
Final

In Sonic 3, the sign frames are uncompressed and loaded dynamically over each other to conserve video memory. This said, also present in the game's data is an unused copy of the same art compressed like in Sonic 2, strongly suggesting it is from earlier in development.

Although Sonic, Tails, and Robotnik are basically the same as their Sonic 2 counterparts, Knuckles appears for the first time, with a slightly different appearance relative to the final art. This early version is still present in Sonic & Knuckles.

Hidden Placeholder Tiles

Various numbers and letters are loaded in and replaced with animated stage tiles. Curiously, they differ between zones, and some are written in Japanese characters.

Angel Island Zone

Hydrocity Zone

Marble Garden Zone

Carnival Night Zone

Launch Base Zone

Out of Bounds Backgrounds

The background of Azure Lake Zone has a flower garden that can't be seen because the level gets in the way.

Early
Final

Chrome Gadget Zone has a large portion of its background hidden by the stage and palette.

Unused Level Chunks

Several chunks of levels are unused during the game. The chunks are placed starting at address FF8088, and can be inserted into levels by entering the given values into FF8088:XX. Most of them have no noticeable differences from used chunks.

Angel Island Zone

Act 1:

• 

  D0

• 

  D5

• 

  E9

Hydrocity Zone

Act 2:

• 

  1E

• 

  29

• 

  D8

Marble Garden Zone

Act 2:

• 

  CB

• 

  E3

• 

  E9

• 

  FA

Carnival Night Zone

Acts 1 and 2:

• 

  7D

• 

  9D

• 

  50

• 

  51

• 

  59

• 

  90

• 

  B2

IceCap Zone

Act 1:

• 

  2C

• 

  2D

• 

  39

• 

  A8

• 

  BD

• 

  BE

Act 2:

• 

  AB

• 

  5C

• 

  6E

• 

  9B

• 

  AB

• 

  BD

Acts 1 and 2:

• 

  D1

Launch Base Zone

Act 1:

• 

  7E

• 

  8F

• 

  56

• 

  88

• 

  D6

• 

  D7

• 

  DB

• 

  F1

• 

  F9

• 

  FD

• 

  FE

Act 2:

• 

  32

• 

  A6

• 

  A7

• 

  B2

Acts 1 and 2:

• 

  24, This chunk was used in the Act 1 Bossroom in the November 3rd 1993 Prototype. It would have been used with chunk 23, which was later changed into a generic ceiling chunk, and it would warp you up to the top of the bossroom allowing you to reach two separate platforms in which you could hit the boss.

• 

  DA

Unused Audio

Music

Most of the music from Sonic & Knuckles can be played from the Level Select/Sound Test.

Sound ID	Song	Comments
$09		Flying Battery Zone Act 1. The loop point in the "echo" track of the lead instrument is set slightly later than the rest of the tracks; as a result, it falls further and further out of sync every time the song loops. This was fixed in Sonic & Knuckles and its lock-on.
$0A		Flying Battery Zone Act 2.
$0F		Mushroom Valley/Hill Zone Act 1.
$10		Mushroom Valley/Hill Zone Act 2.
$11		Sandopolis Zone Act 1.
$12		Sandopolis Zone Act 2.
$13		Lava Reef Zone Act 1.
$14		Lava Reef Zone Act 2/Hidden Palace Zone.
$15		Sky Sanctuary Zone.
$16		Death Egg Zone Act 1. For some odd reason, this plays in Sky Sanctuary Act 2 in Sonic 3 alone.
$17		Death Egg Zone Act 2. Death Egg Zone uses this for acts 1 & 2 in Sonic 3 alone.
$18		Sonic & Knuckles Act 1 Boss. This can be heard while fighting any Hydrocity Zone boss if you jump out of the water after the drowning music starts.
$1A		The Doomsday Zone.
$1B		Glowing Spheres Bonus Stage.
$1D		Slot Machine Bonus Stage. Oddly, the unused Glowing Spheres Bonus Stage in Sonic 3 alone uses this music.

(Source: Sonic Retro)

Sound Effects

Many of these sound effects would see use in Sonic & Knuckles, though some of these sounds would also be unused there.

Sound ID	Sound	Comments
$3A		This is a shield sound leftover from Sonic the Hedgehog 2.
$40		Unused; sounds like an electric zap. This sound would later be used for the Thunder Shield in Sonic Generations and Sonic Lost World, suggesting that it may have been an early sound effect for the Thunder Shield. The Phantom Egg also uses this sound for its barrier in Sonic Mania.
$53		Laser charging sound, used for the Flying Battery Zone laser boss and the jumping spike balls in Lava Reef Zone Act 2.
$54		Laser firing sound, used for the Flying Battery Zone laser boss.
$55		Sound effect used when a brick in Sandopolis Zone goes across a line of black rotating circles.
$5A		Unused; sounds like something revving up. This sound effect would see use in Sonic 3D Blast.
$5C		The sound of Mecha Sonic short-circuiting after it's defeated.
$69		The sound that plays when you push a brick in Sandopolis Zone.
$6B		Unknown, possibly unused; sounds like a higher-pitched version of the sound heard when hitting an R, Up or Down block in the Special Stage from Sonic 1.
$6D		Unused; sounds like a door closing.
$71		Duplicate of $3A; another shield sound leftover from Sonic the Hedgehog 2.
$7A		The sound of the Lava Reef Act 2 boss emerging from lava.
$7C		Used by the magnetized platforms in Flying Battery Zone.
$7D		Unused; sounds like mild rattling.
$84		Unused; sounds like something charging up. Only seems to be referenced in some zone with a high level ID which is composed of garbage data.
$85		Unused; sounds like it would have been used in cooperation with $84.
$87		The sound that plays when you bounce on a mushroom in Mushroom Hill Zone.
$88		Mushroom Hill Zone elevator sound.
$89		Mushroom Hill Zone satellite dish (from Dr. Robotnik's season-changing machine).
$8A		The sound the ghosts from Sandopolis Zone make when they vanish.
$8B		The sound of the Mushroom Hill miniboss chopping a log.
$8C		The sound of the Mushroom Hill miniboss struggling to chop a log.
$8D		Unknown, possibly unused; a very quiet sound. Could have been used as waterfall ambience like in Sonic 1?
$8E		Unused; another electric rev-up sound.
$8F		The sound the door on the pyramid in Sandopolis Zone makes when it opens.
$90		Door closing sound from Sandopolis Zone, and also the sound of Knuckles hitting the ground after his defeat.
$92		Ghost sound effect from Sandopolis Zone.
$93		The sound that plays when the armor on Dr. Robotnik's golem machine comes back on. This sound was reused later in Sonic Mania as the sound for the Green Hill Zone Act 1 boss spinning.
$95		The sound of the giant hand appearing to attempt to crush you in the Lava Reef miniboss.
$96		The sound the giant spikeballs in Lava Reef Zone make when they roll around.
$97		The sound a Toxomister makes when it sprays its toxic gases.
$98		The sound of a falling stalactite in Lava Reef Zone.
$99		Unused; A small "tick" sound.
$9A		The sound of the pop-up springs from Sky Sanctuary Zone.
$9B		A loud bang that plays when the Sandopolis Zone Act 2 boss comes closer to you.
$9C		Sound that plays when a Super Emerald regains its color.
$9D		The sound of the missile reticles in the Lava Reef Act 2 boss. This sound effect is also used by the Green Hill Zone Act 2 boss from Sonic Mania.
$9E		The sound of a platform breaking upon coming into contact with the Lava Reef Act 2 boss.
$A0		The sound of the Lava Reef Act 2 boss firing a missile.
$A1		Unused. A low-humming, unsettling sound. This sound effect is used by the Stardust Speedway Act 1 boss in Sonic Mania.
$A2		The sound of the speed-up launchers in Flying Battery Zone and Death Egg Zone.
$A3		Death Egg Zone lift platform sound effect.
$A4		The sound that Mecha Sonic makes when he goes super.
$A5		Unused; sounds like something rising or powering up?
$A6		Unused; another dashing noise.
$AE		The sound that the seesaw mushroom from Mushroom Hill Zone makes when the black weight lands on it. This sound is also used in the Bonus Stages in Sonic & Knuckles.
$B5		A leftover from Sonic 1 that was used for the breakable diamonds in the Special Stage. Might have been used for the Slot Machine Bonus Stage which is based off that Special Stage.
$BC		Unused? Possible waterfall sound effect.
$C2		The sound of the flamethrowers in Flying Battery Zone and Lava Reef Zone.
$C4		The sound Red Eye makes when it gets angry.
$C5		Unused; sounds like it would be used in coordination with $C4.
$CA		The sound of the light beam transportation systems in Death Egg Zone.
$CE		The gusts of wind from Mushroom Hill Zone. Also used in Knuckles' ending after Super Mecha Sonic explodes.
$CF		A louder version of $CE that might be unused even in Sonic 3 & Knuckles.
$D1		Possibly unused; another very faint sound that may sound like static.
$D3		Used in Sonic & Knuckles when the Death Egg flies through Sky Sanctuary zone; sounds like a quiet version of $CD.
$D4		Used by the bouncing puzzle room in Death Egg Zone.
$D5		Used when the lava falls from Lava Reef Zone. Repeatedly pressing the C button when playing this sound in the Sound Test makes it play longer.
$D6		Unknown/unused; rumbling/electric sound?
$D7		The sound of the elevators in Lava Reef Zone and Death Egg Zone.
$D8		Unused; sounds like a screeching warning siren. Repeatedly pressing the C button when playing this sound in the Sound Test makes it play longer. It was used in the November 3th 1993 prototype when Robotnik appeared behind the trees at the end of Angel Island Zone Act 2.
$D9		The sound the electromagnets in Flying Battery Zone and the black gravity spheres in Death Egg Zone make.
$DA		The sound of the wind trap Knuckles activates in Mushroom Hill Zone.
$DC - $DF		All of these sounds are duplicates of $DB (heard when running across water in Hydrocity Zone) and are likely placeholders. Sonic & Knuckles replaces $DC with its credits medley.

Unused Palettes

Sonic 2 SEGA Screen:
The color palettes of the Sonic 2 SEGA screen are abandoned in offset 08C134.

Sonic 2 Title Screen:
Sonic and Tails' color palettes from the title screen are located in offset 08C1B4.

Sonic 2 Prototype Level Select:
For some obscure reason, it is still possible to see the color palettes from the level select screen of the Sonic 2 prototypes in offset 08C1D4.

Early Launch Base Zone Act 2 Water:
This color palette set does not include colors for Sonic underwater, which suggests it would be used after some cutscene or scene change in Launch Base Zone. There is little difference in the colors, nothing too important. It closely matches up with the November 3rd 1993 Act 2 water palette. It can be found at offset 08CB14.

November 3rd 1993 Palette
Unused Palette

Glowing Spheres Bonus Stage:
An old version of the Sonic & Knuckles Bonus Stage color palette can be found in offset 08CDB4. It is exactly the same as the Sonic 3C 0408 and the Sonic 3 November 3rd prototype.

Slot Machine Bonus Stage:
This palette is quite different from the Sonic & Knuckles prototypes, and can be seen in offset 08CE14. It is exactly the same as the Sonic 3 November 3rd Prototype.

Lava Reef Zone cycle 1:
This palette cycle would have been used for animating the Lava, it can be seen if Lava Reef is accessed in Sonic 3. There are no notable differences from the S&K version. It can be found at offset 002EFE.

Lava Reef Zone cycle 2:
This palette cycle would have been used for the dark glowing rocks, and it can be seen if Lava Reef is accessed in Sonic 3. There are no notable differences from the S&K version. It can be found at offset 002F7E.

Palette duplicates:
These palettes can be found at offsets 05275C and 05277C. They are copies of the palettes used in Angel Island Zone Act 2 and IceCap Zone Act 2, respectively.

Unused Knuckles 1-Player palette
The palette that is used for Knuckles in Sonic & Knuckles and this game's lock-on version is abandoned at offset 08C2F6.

Scrolling Credits

The game contains an unused, unfinished scrolling credits routine, which can be activated by setting RAM address FA87 to 2 during the credits sequence , or just use the code FFFA87:0002. The actual credits were apparently not yet in place when this was abandoned, as it scrolls small and large versions of the letters B-F, and then abruptly fades to the Sonic 3 logo screen. The final staff roll simply fades between static pages of text.

Unused Areas

Hydrocity Zone Act 1

The starting corridor from Act 2 is present in the Act 1 layout; even though it gets overwritten and ends up unused.

Carnival Night Zone Act 1

A long unused corridor in Act 1 that starts at coordinate 3400 to 3800 at the high 04AC is very similar to Act 2 when Act 1 is rewritten after the fight against the mini-boss. However, this corridor is at a height above the rewritten area and is never seen.

Carnival Night Zone Act 2

There is a long vertical shaft at the very end of the level. It leads down into a bottomless pit. The shaft serves no apparent purpose and is never seen normally.

Knuckles' ending area and teleporter are all still intact. The teleporter is non-functional however.

IceCap Zone Act 1

Knuckles' starting location can still be found in IceCap Zone even though it goes unused.

Launch Base Zone Act 1

A small level section and spring are in the Launch Base Act 1 layout. Just like Hydrocity Zone, they are completely useless and are never seen because they are overwritten by the Act 2 layout.

Oddities

Misplaced Objects

There are 3 "end-of-act monitors" hidden in the boss area in the Carnival Night Zone Act 2 contain 10 rings each, curiously there are also monitors in the area of the boss on Angel Island 2 on the way to Knuckles. This is still a total mystery.

A piece of bridge can be found inside the walls of Hydrocity Zone Act 2.

An ice spike can be found inside the walls of the IceCap Zone Act 1. Near the end of the zone.

There is a ring on the out of bounds of the Bonus Stage, curiously it has been removed from Sonic 3 & Knuckles.

Carnival Night Zone Palette

Pre-release screenshot	In-Game

Applying Launch Base Zone Act 2's underwater palette to Carnival Night Zone results in a color scheme identical to that seen in the Nov 3, 1993 prototype and a screenshot of the level found in pre-release material.

(Source: Sonic Retro)

Knuckles' Theme

Knuckles' theme is just a set of drums that lasts for roughly four seconds, and loops forever. However, at around the 34-second mark is a brief voice sample before the next section of drums. This in and of itself isn't particularly interesting, but it should also be noted that whenever the song plays in-game it's always in scripted events; the song only ever plays for a maximum of 10 seconds or so. The only way to listen to this small sample is to use the sound test, jump just before the bridge collapses in the transition from Angel Island to Hydrocity and land on the piece of land that you fought the boss on and listen to it there, or wait after Knuckles bombs the building near the end of Launch Base Act 1.

100000 Points!

While not technically unused, the circumstances to get this would be nearly impossible. Beating a level with a time of 9:59 (1 second from getting a time over) will award the player 100000 points; this also is intentional according to the code.

It would return years later in Sonic Mania.

Changes in Sonic 3 & Knuckles

When locked-on to Sonic & Knuckles, a number of changes were made, either to fix bugs or weird design choices.

Knuckles Art Changes

Sonic the Hedgehog 3	Sonic & Knuckles

The Sonic and Knuckles version of his running sprite ended up being polished to be two pixels shorter and fix some of the leftover torso drawing from Sonic's sprite (though they didn't do a good job, as some tan pixels are still present and the diagonal versions weren't changed at all)

(Source: Sonic 3 Unlocked)

Bugs in Sonic 3 Alone

• Due to an oversight, Super Sonic decelerates very fast when rolling.
• In Sonic 3 alone, Super Sonic can bubble bounce, which isn't meant to happen.
• If the W Spin Attack/Insta-Shield animation finishes after Sonic lands on the floor, using it on the next jump won't increase his attack radius.
• For some reason, Checkpoints aren't cleared when returning to the level select in Sonic 3 alone.
• The Bonus Stage title-card will read "Doilus Stage" if the player attempts to quit back to the level select.
• The Big Shaker miniboss in Hydrocity incorrectly plays the Act 2 boss theme, and jumping out of water when you're about to drown will play the Sonic & Knuckles miniboss theme; the latter wasn't necassarily fixed as it's still calling the Sonic 3 miniboss theme, however in Sonic 3 & Knuckles both miniboss themes are the same.
• Tails doesn't have a collision with the wall at the beginning of Hydrocity Act 2.
• It's possible to outrun the trigger to lock the camera at the boss in Hydrocity Act 2. Though this isn't recommended as breaking the capsule will softlock the game.
• The Screw Mobile can glitch out Super Sonic.
• If the Tunnel Bot is defeated too early in Marble Garden Act 2, the game will crash due to the camera being too far away, causing Act 2's level layout to overwrite everything in memory.
• Tails can spawn in weird positions at the beginning of Carnival Night Act 2.
• A ceiling corner in Carnival Night Act 2 has a faulty collision. Should Super Sonic jump into the wall-to-ceiling transfer and run along with the ceiling, he will be stuck in the ceiling, unable to escape.
• If the player glitches Super Sonic into Knuckles' path in IceCap act 1, it's possible for the ice obstacles to hurt him.
• In IceCap Act 1, Tails will die on the first slide. It can be "fixed" by touching the first checkpoint then dying on purpose, or by reaching the first Special Stage (something that's mentioned below the infamous "Eggman's Diabolical Traps" section.
• Super Sonic can be hurt by Big Arms.
• It's possible to clip through the loop in Balloon Park.

(Source: Sonic 3 Unlockedfor the Insta-Shield glitch)

(Source: Sonic Retro)

Stages

To do: There are still more differences.

Hydrocity Zone

Sonic the Hedgehog 3	Sonic 3 & Knuckles

The beginning of Hydrocity Zone Act 2 went through some layout changes that mostly reduced difficulty.

Marble Garden Zone

Sonic the Hedgehog 3	Sonic 3 & Knuckles

In Sonic 3 & Knuckles, a lot of extra objects were added to this room in Act 2 to prevent Knuckles from taking Sonic and Tails' path; the most important object is the GTGT collision block to prevent Knuckles from climbing the wall and hitting the Relief's eye.

IceCap Zone

• In Act 1, the snow pile that falls on Sonic and Tails in the pit where they enter the cave is not solid in the standalone Sonic 3, but it is in S3&K and it requires the player to jump to get out from it and it can be walked on.

Sonic the Hedgehog 3	Sonic 3 & Knuckles

Originally, this was a Sonic & Tails or Tails only path. Sonic 3 & Knuckles added a trampoline so that Sonic can go up there without Tails' help.

Launch Base Zone

Sonic the Hedgehog 3	Sonic 3 & Knuckles

Knuckles's boss arena was edited in Sonic 3 & Knuckles. The most notable difference is the position of the Twin Hammer/Swing’m Spikez boxes.

Sonic the Hedgehog 3	Sonic 3 & Knuckles

This is another notable difficulty change, as this area is very hazardous in Sonic 3. The player would have to avoid breaking the Eggman monitors and enter a room full of spikes to hit the door switch. Sonic 3 & Knuckles moves the switch outside, and turns the room into a bonus room with two Super Ring Monitors. However, hitting the switch will block off the monitors.

Sonic the Hedgehog 3	Sonic 3 & Knuckles

A simple monitor subtype change from a harmful Eggman to a helpful Invincibility.

(Source: Sonic 3 Unlocked)

Regional Differences

Unlike other Mega Drive/Genesis Sonic games (including Sonic 3 & Knuckles), Sonic 3 "alone" is region-locked and each region got a separate version.

One difference between the Western and the Japanese release, like Sonic 2, is the name used for Tails (e.g. Tails for US/Europe, Miles for Japan). However, the only change made here is changing Tails to Miles on the Act results; his life counter still says Tails. This was fixed in Sonic 3 & Knuckles.