Sonic the Hedgehog 2 (8-bit)/Hidden content

From Sonic Retro

Back to: Sonic the Hedgehog 2 (8-bit).

Level select


When turning on the game hold UpLeft+12 until 2 ring noises chime.

Extra acceleration

Pressing Left and Right at the same time on the D-Pad will result in incredible acceleration and speed to the left. This is mainly useful in emulation (and has been extensively used in the Tool-Assisted Speedrun), while it's unfeasible on a real unmodified console.

Unused content


Art Description
Some unused sprites of Tails crying. Probably meant to be used in the ending cutscene when he is rescued.
These three animations are from Sonic 1 for the Master System, but were found in Sonic 2 for the Game Gear.
Sonic's death sprite from the Master System version of Sonic 1.
UZ Boss.png
The entire body of the Under Ground Zone boss can be seen here. Normally only its head is visible.
The entire body of the Sky High Zone boss was also drawn. Normally only its head and neck can be seen.
Sonic monitor. This one isn't really unused; you can find it hidden in a wall in Crystal Egg Zone, but the graphics are obscured. When collected, it grants a Continue.
Question mark monitor, possibly set to give the player a random amount of rings or items, like in the 2-player mode of Sonic 2 for Mega Drive.
Grey Sneaker monitor which might have slowed you down, similar to the Slow sneaker in Sonic 3's 2-player mode.
This could have been a checkpoint marker, like the 8-bit version of Sonic 1.
UZ bricks.png
Under Ground Zone Bricks.
UZ loop.png
The remains of Green hill zone style tubes for Under Ground Zone.
Miscellaneous Under Ground Zone tiles.
UZ platform.PNG
Under Ground Zone floating platform.
Sky High Zone boulder, probably meant to roll down a hill in act 1.
S2 8bit skyhigh platform.png
Sky High Zone platform.
S2 8bit skyhigh block.png
Sky High Zone object - probably another platform.
Unused Aqua Lake Zone tile.

Gimmick Mountain name


Originally the level card for Gimmick Mountain wasn't going to have a shortened name. Hivebrain discovered the word "Mountain" within the ROM. Due to lack of space on the screen Mountain was shortened to Mt.

Cheat device codes

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

Game Genie

Official codes, Game Gear version

Code Effect Reference
009-04F-3BE Infinite lives.
012-B8D-E66 Start with 1 life.
052-B8D-E66 Start with 5 lives.
092-B8D-E66 Start with 9 lives.
A78-92C-19E Invincible after 1 ring (Except on act 3).
026-5ED-E6E Each ring worth 2.
036-5ED-E6E Each ring worth 3.
046-5ED-E6E Each ring worth 4.
056-5ED-E6E Each ring worth 5.
066-5ED-E6E Each ring worth 6.
076-5ED-E6E Each ring worth 7.
086-5ED-E6E Each ring worth 8.
3A7-E4C-2A2 Don't lose rings when hit.
001-12D-3B7 Stop timer.
3E2-E4D-3B4 + 012-E5D-E69 Start on Act 2.
3E2-E4D-3B4 + 022-E5D-E69 Start on Act 3.

Pro Action Replay

Unofficial codes, Game Gear and Master System version 1.0 and 2.2

Code Effect
00D3A9:15 Become Invincible After Being Hit.
00D298:09 Infinite Lives.
00D299:63 Infinite Rings (Press button 1 at end of level during score totaling).
00D2BA:00 Keeps Time At Zero (Minutes).
00D2B9:00 Keeps Time At Zero (Seconds).
00D295:0? Zone Select (Enable switch after the first 2 screens but before the level starts, after the level starts disable).
  • 0: Underground
  • 1: Sky High
  • 2: Aqua Lake
  • 3: Green Hills
  • 4: Gimmick Mountain
  • 5: Scrambled Egg
  • 6: Crystal Egg
00D296:0? Act Select (Enable switch after the first 2 screens but before the level starts, after the level starts disable).
  • 0: Act 1
  • 1: Act 2
  • 2: Act 3
00D502:13 Start with Glider.


Sonic the Hedgehog 2 (8-bit)
S2 sms title.png

Main page

Promotional material
Magazine articles

Hidden content
Hacking guide