View source for Sonic & Knuckles/Hidden content

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{{Outdated}}
==Level select==
{{HiddenContent
| image1=SK level select.png
| desc=While in [[Mushroom Hill Zone]], jump on to one of the pulley systems, then press {{left}} {{left}} {{left}} {{right}} {{right}} {{right}} {{up}} {{up}} {{up}}. A [[Ring]] sound will confirm correct entry. Press {{start}}, then {{A}} to return to the title screen. Press {{A}}+{{Start}} to go to the Level Select screen.

Though the ''[[Sonic the Hedgehog 3]]'' [[Zone]]s are listed, they are not available unless ''Sonic 3'' is locked-on; selecting any of them will load Mushroom Hill Zone Act 1. The player's character can be chosen by pressing {{C}}, though selecting '''00''' or '''02''' (normally associated with [[Miles "Tails" Prower|Tails]]) will override the player's character to [[Sonic the Hedgehog|Sonic]].
}}

==[[Debug mode]]==
{{HiddenContent
| image1=S&K MD DebugMode.png
| desc=Contrary to popular belief, there IS a debug mode available for this game. ''[[Sonic the Hedgehog 3 & Knuckles]]'' runs on the codebase of ''Sonic & Knuckles'' which has a separate check to enable a debug mode cheat code in place of the level select code in Mushroom Hill when ''Sonic 3'' is locked on. To use debug mode purely in ''Sonic and Knuckles'', the player needs to overwrite the memory of the game while a ''Sonic 3'' cartridge or ROM is locked on. Simply start up ''Sonic 3 & Knuckles'', unlock the level select and debug mode codes for that game and then highlight any level in the Sound Test, hold {{A}}, press {{Start}}, and release {{A}} when Sonic appears. Switch to an "S" [[Monitor]], and paste a big amount of monitors until sprites begin to flicker. Then revert back to Sonic, and [[Spin Dash]] or jump straight into the monitors. Due to how the game loads its art, the game will break, crash or reset to demo mode. If the game has not crashed yet, press {{start}}, and then press {{A}} if necessary. The game may ignore any flags for a ''Sonic 3'' cartridge being detected and it will boot up into ''Sonic & Knuckles'' mode, redirecting the player to the ''Sonic & Knuckles'' title screen. Choose any character, hold {{A}} then press {{start}} to go to the level select screen. Highlight any level, hold {{A}}, then press {{start}}.

During gameplay:
*Press {{A}} to reverse gravity when in normal mode.
*Press {{C}}+{{B}} to cycle through all mapping frames of the character when in normal mode.
*Press {{B}} to toggle normal and debug mode.
**Press {{A}} to advance forward through the debug object list.
**Press {{A}}+{{C}} to advance backwards through the debug object list.
**Press {{C}} to place the selected object at the current coordinates.
*During pause press {{A}} to fade to black and restart from the SEGA screen.
*During pause press and hold {{B}} to enable slow-motion (this proceeds at half-speed for as long as the {{B}} button is held down).
*During pause press {{C}} to advance one frame.
*Current coordinates are designated by the top line of hex digits in the HUD.
*Viewport coordinates are designated by the bottom line of hex digits in the HUD.
}}

==Eighth Special Stage==
{{HiddenContent
| image1=SonicandKnuckles MD SpecialStage 8 Start.png
| image2=S&KSS8.png
| desc=If [[Sound Test]] is enabled, and any of the "[[Special Stage (Sonic the Hedgehog 3 & Knuckles)|Special Stage]]" options is selected, Sonic or Knuckles is taken to the first Special Stage. The end of it however, spawns a yellow [[Super Emerald]]. This is when the special stage is marked as clear, but the normal Chaos Emerald amount doesn't rise. The Super Emerald amount will rise, but it has pretty much no effect due to Super Emeralds being unobtainable in ''Sonic & Knuckles'' alone. This bug will allow access to a hidden Special Stage and allow for the 8th Emerald to be collected once the other six have, though.

It is also possible to access this Special Stage by enabling debug mode above, then setting the Sound Test selection to '''07''' and pressing {{A}}+{{Start}} while selecting any of the Special Stage options. 
}}

==Hidden area of [[Hidden Palace Zone (Sonic & Knuckles)|Hidden Palace Zone]]==
{{HiddenContent
| image1=Sonic3kmonitors.png
| image2=SnK_HPZ_SecretAreaRight.png
| desc=When using [[edit mode]] in [[Hidden Palace Zone (Sonic & Knuckles)|Hidden Palace Zone]], an area above and to the left of Sonic's fight with Knuckles contains a selection of [[monitors]]; six on the left, and three on the right. In ''Sonic 3 & Knuckles'', Tails can fly up to this area.

It has been suggested that these could have been placed here so that clean screenshots could be taken for the Japanese manual. The manual clearly shows Sonic bubble bouncing in Hidden Palace, despite no [[Water Shield]]s being available through normal play{{fileref|S&K MD JP manual.pdf|page=22}}{{fileref|S&K MD JP manual.pdf|page=23}}.
}}

==Bow to Knuckles==
{{HiddenContent
| image1=SonicandKnuckles MD SSZBow.png
| desc=After Knuckles has let the player across in [[Sky Sanctuary Zone]], if the player stands in a certain spot and ducks with {{down}}, Knuckles turns around and gives a "get going" gesture.
}}

==Unused content==
===Art===
{{UnusedTable|type=Art|
{{UnusedRow
| content={{SpriteImage|S&K MD Sprite KnucklesHanging.gif}}
| desc=Vertical hanging sprites for Knuckles in Mushroom Hill Zone Act 2.
}}
{{UnusedRow
| content={{SpriteImage|S&K MD Sprite KnucklesDeathB&W.png}}
| desc=A monochrome death sprite for Knuckles.
}}
{{UnusedRow
| content={{SpriteImage|S&K MD Sprite HeyHo Early.png}}
| desc=An unused, slightly different version of [[Hey Ho]].
}}
{{UnusedRow
| content={{SpriteImage|Sonic3 MD Sprite FBZ2BossHeads.png|crop_width=32}}
| desc=An unused frame for [[Eggman]] for use with the [[Hang Mobile]] when attacking, but it doesn't appear due to a programming oversight.{{ref|https://s3unlocked.blogspot.com/2017/10/non-standard-eggheads-part-1.html}} [[sega:Action Replay (Mega Drive)|Pro Action Replay]] code '''067C04:0829''' will re-enable it.
}}
{{UnusedRow
| content={{SpriteImage|S&K MD Sprite EggGolemPiece.gif}}
| desc=An unused piece of the [[Egg Golem]] boss. Its sprite is loaded and the object has a sub-value to load it.
}}
{{UnusedRow
| content={{SpriteImage|S&K MD Sprite EggroboJumping.png}}
| desc=A jumping frame for [[Eggrobo]].
}}
{{UnusedRow
| content={{SpriteImage|SnKSSJackpot.png}}
| desc=Slot machine image for [[Super Sonic]], intended for the Slot Machine [[Bonus Stage (Sonic the Hedgehog 3 & Knuckles)|Bonus Stage]].
}}
{{UnusedRow
| content={{SpriteImage|SnKSball.gif}}
| desc=A flashing S gumball. One could presume it has something to do with [[Super Sonic]].
}}
{{UnusedRow
| content={{spriteImage|SnKPalmtree.jpg}}
| desc=Unseen palm tree graphics. Although these tiles are used in both ''Sonic 3'' and ''Sonic 3 & Knuckles'' in the introduction to [[Angel Island Zone]], they are hidden behind leaf sprites. This is how it looks with the sprites layer disabled:<br>[[File:SecretPalmtree.png]]
}}
}}

===Objects===
====Placeable in [[edit mode]]====
{{UnusedTable|type=Art|
{{UnusedRow
| content={{SpriteImage|Sonic3K MD Sprite Monitors.png|crop_width=28|crop_x=140}}
| desc=An "S" [[monitor]]. This transforms Sonic and Knuckles into [[Hyper Sonic]] and [[Hyper Knuckles]] respectively, both of which are normally reserved for ''Sonic 3 & Knuckles''.
}}
{{UnusedRow
| content={{SpriteImage|S&K MD Sprite LRZ2SteppingStone.png}}
| desc=A lava stepping stone for the second Act of [[Lava Reef Zone]]. Similar objects exist in Act 1, but this unique art for Act 2 is never seen.
}}
{{UnusedRow
| content={{SpriteImage|SnKplatform.png}}
| desc=A platform for the Glowing Spheres [[Bonus Stage (Sonic the Hedgehog 3 & Knuckles)|Bonus Stage]].
}}
{{UnusedRow
| content={{SpriteImage|SnKFball.png}}
| desc="F" gumball, placeable in Glowing Spheres [[Bonus Stage (Sonic the Hedgehog 3 & Knuckles)|Bonus Stage]]. When collected it makes the same noise as a Bumper Ball, but it doesn't do anything.
}}
}}

====Others====
{{UnusedTable|type=Art|
{{UnusedRow
| content={{spriteImage|SnKHoloscreen.gif}}
| desc=A rotating holograph of the Death Egg. It can be found by hex-editing a savestate of Death Egg Act 2. At address '''A500''' replace '''01''' with '''E5''' and the most northwestern piece will change to this. Thanks to [[Gold]] for finding this.
}}
{{UnusedRow
| content={{SpriteImage|S&K MD Sprite FlashingPocket.gif}}
| desc=A solid block that uses art for the slot in the Slot Machine Bonus Stage.
}}
}}
===Audio===
{{UnusedTable|type=Audio|
{{UnusedRow
| content=
| desc=A "game clear" jingle for ''Sonic & Knuckles'' at sound ID '''32'''. Though ''Sonic 3'' used this ID for its own jingle played during the ending, it isn't used in ''Sonic & Knuckles'' at all. A longer version of this jingle can be heard at the end of the credits medley.
}}
}}

===Tails===
{{HiddenContent
| image1=Tails in S&K.png
| desc=Tails is playable in the game through hacking. Unfortunately, most of his sprites are missing. {{file|Sktails.zip|A savestate}} of Tails in ''Sonic & Knuckles'' is available. If the PAR code FFFF09:02 is used in ''Sonic & Knuckles'', Tails will be usable, but just about every sprite of his, except the transformation sprite, will be missing, basically rendering him invisible (unlike when a savestate is used; a different, glitchy sprite is used in place of Tails's original one). However, his sprites used at the end of Sky Sanctuary Zone to run around the collapsing pillar are actually stored in the Sonic & Knuckles' ROM and therefore are visible. The same sprites are used also in the same context in Lava Reef Zone.
}}

==Misplaced objects==
===Flying Battery Zone Act 1===
{{HiddenContent
| image1=Sonic&Knuckles MD FBZ1 MisplacedSprings.png
| desc=There are two yellow springs buried in the ground near the first giant purple tube which are unreachable. 
}}
===Death Egg Zone Act 1===
{{HiddenContent
| image1=Sonic&Knuckles MD DEZ1 MisplacedRings.png
| desc=There are three [[Ring]]s placed in the floor under the first black anti-gravity orb. It is possible to collect these Rings by returning to this point with a [[Lightning Shield]].
}}

==Cheat device codes==
These are cheat codes that can only be used with game enhancer devices. Support for these codes is available in most emulators.

===[[Game Genie (Mega Drive)|Game Genie]]===
==== Official Codes, Sonic & Knuckles Alone ====
{|class="prettytable"
! Code !! Description !! Works in S&K !! Works in S3K
|-
! colspan="4" | General codes
|-
|AFKT-AAG0
|Start with 1 life.
| {{Yes}}
| {{No}}
|-
|AKKT-AAG0
|Start with 2 lives.
| {{Yes}}
| {{No}}
|-
|AVKT-AAG0
|Start with 4 lives.
| {{Yes}}
| {{No}}
|-
|AZKT-AAG0
|Start with 5 lives.
| {{Yes}}
| {{No}}
|-
|A7KT-AAG0
|Start with 7 lives.
| {{Yes}}
| {{No}}
|-
|BFKT-AAG0
|Start with 9 lives.
| {{Yes}}
| {{No}}
|-
|DFKT-AAG0
|Start with 25 lives.
| {{Yes}}
| {{No}}
|-
|GKKT-AAG0
|Start with 50 lives.
| {{Yes}}
| {{No}}
|-
|NPKT-AAG0
|Start with 99 lives.
| {{Yes}}
| {{No}}
|-
|K2WA-CA4J
|Infinite lives.
| {{Yes}}
| {{Yes}}
|}

==== Official Codes, Sonic the Hedgehog 3 Locked-on ====
{|class="prettytable"
! Code !! Description !! Works in S&K !! Works in S3K
|-
! colspan="4" | General codes
|-
|AWXT-CA4C
|Don't lose rings when hit.
| {{Yes}}
| {{Yes}}
|-
|HXRT-AA6A
|Infinite time.
| {{Yes}}
| {{Yes}}
|-
|96BA-CAG6 + 98MA-CAF0
|Keep elemental shields when hit.
| {{Yes}}
| {{Yes}}
|-
|AKVT-AA76 + AMNA-EA24
|Keep rings between levels.
| {{Yes}}
| {{Yes}}
|-
|RHJA-E60L
|Bonus round always activated after every checkpoint.
| {{Yes}}
| {{Yes}}
|-
|RGSA-A6YY
|Only 1 blue sphere needed to get a chaos emerald.
| {{Yes}}
| {{Yes}}
|-
|ALNA-AACR
|Rings worth 2 in special stage.
| {{Yes}}
| {{Yes}}
|-
|ARNA-AACR
|Rings worth 3 in special stage.
| {{Yes}}
| {{Yes}}
|-
|AWNA-AACR
|Rings worth 4 in special stage.
| {{Yes}}
| {{Yes}}
|-
|A0NA-AACR
|Rings worth 5 in special stage.
| {{Yes}}
| {{Yes}}
|-
|BLNA-AACR
|Rings worth 10 in special stage.
| {{Yes}}
| {{Yes}}
|-
|NTPT-CA50
|Rings aren't used up as Super (or Hyper) Sonic/Knuckles.
| {{Yes}}
| {{Yes}}
|-
|ACCT-CA2R
|Can't drown.
| {{Yes}}
| {{Yes}}
|-
! colspan="4" | Sonic-specific codes
|-
|RENT-C6YA
|Can always double jump (can't use water shield or become Super Sonic).
| {{Yes}}
| {{Yes}}
|-
|RENT-C6V6
|Can always use Fireball Spin Dash (can't double jump, bounce, or become Super Sonic).
| {{Yes}}
| {{Yes}}
|-
|AANA-CNA0
|Jump a little lower (same height as Knuckles jump).
| {{Yes}}
| {{Yes}}
|-
|4ANA-CRA0
|Jump a little higher.
| {{Yes}}
| {{Yes}}
|-
|2ANA-CWA0
|Jump a lot higher.
| {{Yes}}
| {{Yes}}
|-
|AANA-C4A0
|Jump really high.
| {{Yes}}
| {{Yes}}
|-
|AANA-DYA0
|Jump ridiculously high.
| {{Yes}}
| {{Yes}}
|-
|A2NT-CAG6
|Only 6 chaos emeralds needed to become Super Sonic.
| {{Yes}}
| {{Yes}}
|-
|AYNT-CAG6
|Only 5 chaos emeralds needed to become Super Sonic.
| {{Yes}}
| {{Yes}}
|-
|ATNT-CAG6
|Only 4 chaos emeralds needed to become Super Sonic.
| {{Yes}}
| {{Yes}}
|-
|ANNT-CAG6
|Only 3 chaos emeralds needed to become Super Sonic.
| {{Yes}}
| {{Yes}}
|-
|AJNT-CAG6
|Only 2 chaos emeralds needed to become Super Sonic.
| {{Yes}}
| {{Yes}}
|-
|AENT-CAG6
|Only 1 chaos emerald needed to become Super Sonic.
| {{Yes}}
| {{Yes}}
|-
|AANT-CAG6
|Become Super Sonic without any chaos emeralds.
| {{Yes}}
| {{Yes}}
|-
|NTNT-CAHL
|100 rings needed to become Super Sonic instead of 50.
| {{Yes}}
| {{Yes}}
|-
|FANT-CAHL
|40 rings needed to become Super Sonic.
| {{Yes}}
| {{Yes}}
|-
|DENT-CAHL
|25 rings needed to become Super Sonic.
| {{Yes}}
| {{Yes}}
|-
|BJNT-CAHL
|10 rings needed to become Super Sonic.
| {{Yes}}
| {{Yes}}
|-
|AENT-CAHL
|1 ring needed to become Super Sonic.
| {{Yes}}
| {{Yes}}
|-
|AANT-CAGY + AAPA-CAB8
|Become Hyper Sonic without any emeralds.
| {{Yes}}
| {{Yes}}
|-
! colspan="4" | Knuckles-specific codes
|-
|TB5T-CNCR
|Jumps as high as Sonic (slightly higher than usual).
| {{Yes}}
| {{Yes}}
|-
|PV5T-CRCR
|High jump.
| {{Yes}}
| {{Yes}}
|-
|AB5T-CWCR
|Super jump.
| {{Yes}}
| {{Yes}}
|-
|AB5T-C2CR
|Mega jump.
| {{Yes}}
| {{Yes}}
|-
|AB5T-DTCR
|Orbital jump.
| {{Yes}}
| {{Yes}}
|-
|A36A-CACW
|Only 6 chaos emeralds needed to become Super Knuckles.
| {{Yes}}
| {{Yes}}
|-
|AZ6A-CACW
|Only 5 chaos emeralds needed to become Super Knuckles.
| {{Yes}}
| {{Yes}}
|-
|AV6A-CACW
|Only 4 chaos emeralds needed to become Super Knuckles.
| {{Yes}}
| {{Yes}}
|-
|AP6A-CACW
|Only 3 chaos emeralds needed to become Super Knuckles.
| {{Yes}}
| {{Yes}}
|-
|AK6A-CACW
|Only 2 chaos emeralds needed to become Super Knuckles.
| {{Yes}}
| {{Yes}}
|-
|AF6A-CACW
|Only 1 chaos emerald needed to become Super Knuckles.
| {{Yes}}
| {{Yes}}
|-
|AB6A-CACW
|Become Super Knuckles without any chaos emeralds.
| {{Yes}}
| {{Yes}}
|-
|NV6A-CADA
|100 rings needed to become Super Knuckles instead of 50.
| {{Yes}}
| {{Yes}}
|-
|FB6A-CADA
|40 rings needed to become Super Knuckles.
| {{Yes}}
| {{Yes}}
|-
|DF6A-CADA
|25 rings needed to become Super Knuckles.
| {{Yes}}
| {{Yes}}
|-
|BK6A-CADA
|10 rings needed to become Super Knuckles.
| {{Yes}}
| {{Yes}}
|-
|AF6A-CADA
|1 ring needed to become Super Knuckles.
| {{Yes}}
| {{Yes}}
|-
|AB6A-CACL + AB6A-CAHR
|Become Hyper Knuckles without any emeralds.
| {{Yes}}
| {{Yes}}
|}

====Unofficial codes====
{|class="prettytable"
! Code !! Description !! Works in S&K !! Works in S3K
|-
! colspan="4" | General codes
|-
|RFLA-A6W4
|Enable Level Select ({{A}}+{{Start}} at Title Screen).
| {{Yes}}
| {{No}}
|-
|RFTT-A6XW
|Enable Debug Mode ({{A}}+{{Start}} at Title Screen).
| {{Yes}}
| {{Yes}}
|-
|AVFA-AR74
|Can Access 'Sound Test' Menu From Title Screen.
| {{No}}
| {{Yes}}
|-
|AKEA-CA3W
|Tails never gets tired of flying
| {{No}}
| {{Yes}}
|-
|AA7T-AAM2
|Better night time
| {{No}}
| {{Yes}}
|-
|BCTT-LA3Y + BA8T-NA24
|Knuckles can fight Knuckles.
| {{Yes}}
| {{Yes}}
|-
|ABZT-AA5Y + PKZT-B950
|Tails follows Knuckles.
| {{No}}
| {{Yes}}
|-
|REBA-C6V6
|Invincible against dynamic objects (bullets, enemies, for example), except Knuckles. 	
| {{Yes}}
| {{Yes}}
|-
|RZBA-E6YA
|Invincible against static objects (spikes, for example).
| {{Yes}}
| {{Yes}}
|-
|ABTA-NA7Y
|Invincible against Knuckles.
| {{Yes}}
| {{Yes}}
|-
|PJAA-CA8C
|Destroy enemy upon touching it (except Knuckles).
| {{Yes}}
| {{Yes}}
|-
|ABTT-NA3G
|Damage Knuckles upon touching him.
| {{Yes}}
| {{Yes}}
|-
|AAPT-CAB8
|Don't use up rings to maintain the transformation of any Super/Hyper character.
| {{Yes}}
| {{Yes}}
|-
|CLRA-BA0Y
|Get One Emerald To Get Them All.
| {{Yes}}
| {{Yes}}
|-
|9WSA-BCET 
|Only One Blue Sphere Needed To Win Emerald.
| {{Yes}}
| {{Yes}}
|-
|CXLA-EA7Y
|Bonus stage is always slot machine.
| {{Yes}}
| {{Yes}}
|-
|RHLA-E6ZY + BMLA-EA78
|Bonus stage is always magnetic orbs.
| {{Yes}}
| {{Yes}}
|-
|RHLA-E6ZY + RHLA-E6Z8
|Bonus stage is always gumball machine.
| {{No}}
| {{Yes}}
|-
|REPA-C6YR + REPA-C6YT + REPA-C6YW + REPA-C6YY<br>+ RFJT-C61Y + RFJT-C610 + RFJT-C612 + RFJT-C614<br>+ RF6T-C6V0 + RF6T-C6V2 + RF6T-C6V4 + RF6T-C6V6<br>+ RHPA-C6V0 + RHPA-C6V2 + RHPA-C6V4 + RHPA-C6V6<br>+ RHPT-C6VE + RHPT-C6VG + RHPT-C6VJ + RHPT-C6VL<br>+ RFPT-T6YC
|Disable Super Transformation Music
| {{Yes}}
| {{Yes}}
|-
|NTBT-CB50
|Never Die (except by drowning)
| {{Yes}}
| {{Yes}}
|-
! colspan="4" | Sonic-specific codes
|-
|JAGA-CA98
|Speed shoes don't run out with time.
| {{Yes}}
| {{Yes}}
|-
|AANT-CAHL
|Become Super/Hyper Sonic with 0 rings.
| {{Yes}}
| {{Yes}}
|-
|AANT-CAG6
|Become Super Sonic without collecting Emeralds first.
| {{Yes}}
| {{Yes}}
|-
|AANT-CAGY + AAPA-CAB8
|Become Hyper Sonic without collecting Emeralds first.
| {{Yes}}
| {{Yes}}
|-
! colspan="4" | Tails-specific codes
|-
|JA6T-CA5E
|Speed shoes don't run out with time.
| {{No}}
| {{Yes}}
|-
|ABJT-CACJ
|Become Super Tails with 0 rings.
| {{No}}
| {{Yes}}
|-
|ABJT-CACA
|Become Super Tails without collecting emeralds first.
| {{No}}
| {{Yes}}
|-
! colspan="4" | Knuckles-specific codes
|-
|HKXA-CA7T
|Speed shoes don't run out with time.
| {{Yes}}
| {{Yes}}
|-
|AB6A-CADA
|Become Super/Hyper Knuckles with 0 rings.
| {{Yes}}
| {{Yes}}
|-
|AB6A-CACW 
|Become Super Knuckles without collecting Emeralds first.
| {{Yes}}
| {{Yes}}
|-
|AB6A-CACL + AB6A-CAHR 	
|Become Hyper Knuckles without collecting Emeralds first.
| {{Yes}}
| {{Yes}}
|-
|AB6A-DAJC
|Knuckles can float, push any jump button.
| {{Yes}}
| {{Yes}}
|-
|AP2A-DAR2
|Knuckles Spin dash goes nowhere.
| {{Yes}}
| {{Yes}}
|-
|APYA-DAGC
|Knuckles has a shorter glide.
| {{Yes}}
| {{Yes}}
|-
|AP2A-DAEE
|Knuckles flies upwards.
| {{Yes}}
| {{Yes}}
|-
|1APT-CBHO
|Press down for a chaos emerald
| {{Yes}}
| {{Yes}}
|}

===[[Action Replay (Mega Drive)|Action Replay]]===
====Unofficial codes====
{|class="prettytable"
! Code !! Description !! Works in Gens
|-
|009760:6048
|Red Spheres have no effect in special stages
| {{Yes}}
|-
|0097AE:6672 + 0097C8:4E75
|Collision disabled for bumpers in special stage
| {{Yes}}
|-
|FFFE12:0063
|Always have 99 lives
| {{Yes}}
|-
|FFFE21:0063
|Always have 99 rings
| {{Yes}}
|-
|FFFE25:0000
|Infinite time
| {{No}}
|-
|FFB038:00xx
|Have character ID of (00=Sonic, 01=Tails, 02=Knuckles) (controls things like wall-breaking and character-specific boss fights).
| {{No}}
|-
|FFFF0B:00xx
|Character modifier (00=Sonic & Tails, 01=Sonic, 02=Tails, 03=Knuckles, 04=Blue Knuckles).
| {{No}}
|-
|FFFFE0:0101
|Level select and slow motion enabled.
| {{Yes}}
|-
|00380A:???? + FFF65F:0004
|Sonic Color modifier (found by tailsisdumb; make sure to replace the ???? with any 4-digit number)
| {{Yes}}
|-
|00381E:0006
|Tails is affected by above code (found by tailsisdumb; make sure above code is enabled)
| {{Yes}}
|-
|FFFFDA:0001
|Debug mode always enabled (without holding A during level load)
| {{No}}
|-
|FFE439:0001
|Only one blue sphere required to get the emerald (turn off as soon as special stage HUD appears or else special stage results screen won't register emerald)
| {{No}}
|-
|FFFFB0:0007
|Have 7 Chaos Emeralds.
| {{No}}
|-
|FFFFB1:0007
|Have 7 Chaos Emeralds. Use with the code above.
| {{No}}
|-
|FFFFB0:0707
|Have 7 Chaos and Super Emeralds.
| {{Yes}}
|-
|FFFFB1:0707
|Have 7 Chaos and Super Emeralds. Use with the code above.
| {{Yes}}
|-
|FFFFB2:0?0? + FFFFB4:0?0? + FFFFB6:0?0? + FFFFB8:0?0?
|Emeralds in SRAM modifier. Replace ? with 0 = No Emeralds, 1 = All Chaos Emeralds, 2 = Hidden Palace Emeralds, 3 = Hyper Emeralds. Verified to work in ''Sonic 3 & Knuckles'' only.
| {{Yes}}
|-
|006B68:0A94
|Play as red Sonic (choosing to play as Knuckles produces Sonic with Knuckles' palette) ~courtesy of ShanMan
| {{Yes}}
|-
|FFB15D:FFFF
|Blue Knuckles in first save slot. Save slot should be empty. The Blue Knuckles has Sonic's palette, Knuckles' abilities(floating, etc.), Sonic's Sprite in Special Stage, Labeled as Sonic in Lives. The code is pretty unstable, crashes sometimes.
| {{Yes}}
|-
|FFFF09:0003
|Same as above.
| {{Yes}}
|-
|FFFF09:00xx
|Play as any character regardless of which character is chosen. (00=Sonic & Tails, 01=Sonic, 02=Tails, 03=Knuckles).
| {{No}}
|-
|0119DC:00xx
|Transform into Super Sonic with xx emeralds.
| {{No}}
|-

|valign="top"|FFFE10:XXYY
|Stage/Act Modifier. X=Level; Y=Act. Set Y to 00 for Act 1, and to 01 for Act 2.
{| class="prettytable"
! ID !! Name !! Works in S&K !! Works in S3K
|-
| 00 || Angel Island
| {{No}}
| {{Yes}}
|-
| 01 || Hydrocity
| {{No}}
| {{Yes}}
|-
| 02 || Marble Garden
| {{No}}
| {{Yes}}
|-
| 03 || Carnival Night
| {{No}}
| {{Yes}}
|-
| 04 || Flying Battery
| {{Yes}}
| {{Yes}}
|-
| 05 || Icecap
| {{No}}
| {{Yes}}
|-
| 06 || Launch Base
| {{No}}
| {{Yes}}
|-
| 07 || Mushroom Hill
| {{Yes}}
| {{Yes}}
|-
| 08 || Sandopolis
| {{Yes}}
| {{Yes}}
|-
| 09 || Lava Reef
| {{Yes}}
| {{Yes}}
|-
| 0A || Sky Sanctuary (Act 1 = Sonic / Act 2 = Knuckles)
| {{Yes}}
| {{Yes}}
|-
| 0B || Death Egg
| {{Yes}}
| {{Yes}}
|-
| 0C || Doomsday
| {{Yes}}
| {{Yes}}
|-
| 0D || Sonic/Tails End Sequence (must be set to Act 2)
| {{Yes}}
| {{Yes}}
|-
| 13 || Gumball Machine - Sonic 3 Bonus Stage
| {{No}}
| {{Yes}}
|-
| 14 || Glowing Spheres - S&K Bonus Stage
| {{Yes}}
| {{Yes}}
|-
| 15 || Slot Machine - S&K Bonus Stage
| {{Yes}}
| {{Yes}}
|-
| 16 || Act 1 = Lava Reef Act 2 boss / Act 2 = Hidden Palace
| {{Yes}}
| {{Yes}}
|-
| 17 || Act 1 = 2nd Death Egg Act 2 Boss / Act 2 = Master Emerald Shrine
| {{Yes}}
| {{Yes}}
|-
! colspan="4" | Garbled in 1P, normal in 2P
|-
| 0E || Azure Lake
| {{No}}
| {{Yes}}
|-
| 0F || Balloon Park
| {{No}}
| {{Yes}}
|-
| 10 || Desert Palace
| {{No}}
| {{Yes}}
|-
| 11 || Chrome Gadget
| {{No}}
| {{Yes}}
|-
| 12 || Endless Mine
| {{No}}
| {{Yes}}
|}
| {{Yes}}
|}

==References==
<references/>

{{S&KOmni}}