Sonic & Knuckles/Bugs

From Sonic Retro

Back to: Sonic & Knuckles.

This page documents bugs/glitches that have been found in Sonic & Knuckles. Most of these bugs also apply to Sonic the Hedgehog 3 & Knuckles as the code base is the same.

General bugs

Incorrect monitor palettes

SonicandKnuckles MD KnucklesBubbleShield.png

Monitors are designed to use the blues from Sonic's palette line, so if the player is controlling Knuckles, problems arise. While this issue dates back to using Super Sonic in Sonic the Hedgehog 2 (and is an issue for Super Sonic in Sonic 3 as well as this game), Knuckles is a main character available from the start, and Water Shield monitors are meant to symbolise water.

Curiously a conscious effort to fix shield palettes was made in Knuckles the Echidna in Sonic the Hedgehog 2 (the code for which exists in the ROM of Sonic & Knuckles), but not the main game.

Not fixed in any version.

Level bugs

Mushroom Hill Zone

Act 2 boss sometimes shows as Eggman rather than Eggrobo


Sometimes, Knuckles' boss will have the face of Dr. Eggman rather than Eggrobo as it should. This usually happens after the player loses a life, because it's caused by the game's not having sufficient time during reloading to patch-in Eggrobo's face over Eggman's.

Fixed in Sonic & Knuckles Collection and Sonic Origins.

Flying Battery Zone

Knuckles fights Eggman instead of Eggrobo


While playing as Knuckles in Flying Battery Zone's second Act, the Hang Mobile is piloted by Dr. Eggman instead of Eggrobo. Unlike the above bug, this occurs every time.

This is likely to be due to the game's artists missing this sprite. The battle's perspective is different – the Eggpod and therefore its pilot face the screen head on – and thus requires new animations, which the artists did not implement for Eggrobo.

Fixed in Sonic Origins.

Sandopolis Zone

Spiky pillars and invincibility

SonicandKnuckles MD SpikeyPillars 1.png
SonicandKnuckles MD SpikeyPillars 2.png

If Sonic or Knuckles is standing on one of the moving spiky pillars while invincible, they will remain unharmed when the invincibility wears off. The spikes will only hurt the player if he/she decides to jump on them.

Not fixed in any version.

Push blocks up sand slides

SonicandKnuckles MD SZ SpindashBlock 1.png
SonicandKnuckles MD SZ SpindashBlock 2.png
SonicandKnuckles MD SZ SpindashBlock 3.png

Sonic and Knuckles can push the blocks in Sandopolis Zone by Spin Dashing and holding down Down. Using this method, it is possible to push blocks up sand slides. Sonic and Knuckles will switch to their falling animations, but the block will keep moving upwards. At the top of the slide, the player will switch to their pushing sprite, facing in the opposite direction - letting go at any point will cause the Spin Dash to occur.

Not fixed in any version.

Lava Reef Zone

Exploding Iwamodoki shows 100 points but does not award them


The Badnik Iwamodoki releases a small animal and displays a "100" points score when it explodes, but it does not award points to the player. Perhaps the lack of points – but, of course not the presence of the score notification – is intentional because the player cannot be directly responsible for destroying the Badnik, which instead self-destructs when a character approaches. This might indicate that Iwamodoki was supposed to behave like Asteron, which upon self-destructing neither awards points, displays a notification, nor releases an animal.

Fixed in Sonic Origins. Exploding Iwamodokis now actually award 100 points.

Act 2 palette cycle

Sonic&Knuckles MD LRZ2 Cycle.gif
Sonic&Knuckles MD LRZ2 CycleFixed.gif

The palette cycle that is used for the glowing crystals and pipes in Act 2 suffers from a programming error. Four palette indices are used for the cycle, but the third and fourth indices mistakenly use the same colours as the first and second, rendering half of the intended colours unused and making everything that utilises the cycle look duller. This can be fixed by using Game Genie code ATXT-AAD2[1].

Fixed in Sonic Origins.

Act 2 boss platform palette error

Sonic&Knuckles MD Sprite LRZ2Boss RockPlatform.gif
Sonic&Knuckles MD Sprite LRZ2Boss RockPlatformFixed.gif

The rock platforms seen in the lavafall during Act 2's boss area uses palette 03, which makes the top of the platforms look odd. If these platforms are set to use palette 02 instead, they will match the look of the other platforms seen in the Act, as well as the dark red coloured rocks. This fix can be made by using Game Genie code AGTT-RAX6[1].

Fixed in Sonic Origins. The top of the platforms use palette 02 while the rocks use palette 03.

Bonus Stage

Red Sonic

SonicandKnuckles MD BonusStageRedSonic.png

When Knuckles leaves the Slot Machine Bonus Stage, he briefly becomes a red version of Sonic as the screen fades out.

Not fixed in any version.


Sonic & Knuckles
Sonic & Knuckles title.png

Main page (S3&K|KiS2|Blue Sphere)
Maps (S3&K) (KiS2) (Blue Sphere)

Promotional material
Magazine articles
Video coverage

Hidden content (S3&K)
Bugs (S3&K)
Region coding
Hacking guide