Actions

Sonic the Hedgehog 2 (8-bit)/Bugs

From Sonic Retro

Revision as of 15:03, 31 August 2019 by BSonirachi (talk | contribs) (a good number of frame-perfect bugs in this game)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Back to: Sonic the Hedgehog 2 (8-bit).

General bugs

Increased speed from a rolling jump

Sonic2 SMS Bug RollingJump1.png
Sonic2 SMS Bug RollingJump2.png

If the player jumps while rolling on the ground, they will rapidly gain extra momentum while in the air, more than they normally would if they jumped while running. This even happens if the player rolls off a ledge and holds forward while doing so.

Similar behaviour exists in the Nintendo 3DS version of Sonic Generations.[1]

Not fixed in any version.


Loops

Sonic2 SMS Bug StuckInLoop.png
Getting stuck on a loop.
Sonic2 SMS Bug BackwardsLoop.png
Running backwards through a loop.

Loops in this game have some strange oddities due to the way they are programmed compared to the 16-bit games. If the player runs into them at lower speeds, then there is a chance they can get stuck in the top-right corner. The player is unable to jump off and is thus forced to wait for a Time Over.

Additionally, when running towards a loop, if the player quickly presses Left on the exact frame they start running up the loop, Sonic will run backwards through it and appear to clip through the walls of the loop. The timing for this is very precise, but this is purely a cosmetic bug as the player will still make it through.

Partially fixed in the Game Gear version. The player apparently can't get stuck on a loop, but they can still trigger the animation error.


Invincibility music error

If the player reaches the Signpost while Invincibility is active, and the Invincibility runs out after the Signpost lands, the regular level music will override the clear jingle and play over the results tally.

Not fixed in any version.


Level-specific bugs

Sky High Zone

Stand in the bottomless pit

Sonic2 SMS Bug SHZ BottomlessPit.png

In Sky High Zone Act 1, if the player breaks the Invincibility Monitor at the top of the Act and drops down into the bottomless pit that they must glide over with the Hang Glider, they can walk along the bottom of the pit. Once the Invincibility wears off, however, they can continue to walk along the pit safely until they jump and thus take damage from the hidden spikes in the pit. This behaviour is only in the Master System version of the game.

Fixed in the Game Gear version. The player takes damage immediately after the Invincibility wears off.


Respawning 1UPs

Sonic2 GG Bug Respawning1UP1.png
Roll into this 1UP...
Sonic2 GG Bug Respawning1UP2.png
Then bounce on this spring...
Sonic2 GG Bug Respawning1UP3.png
Stop and backtrack here...
Sonic2 GG Bug Respawning1UP4.png
...and another 1UP appears!

In Sky High Zone Act 2, there is a 1UP Monitor located at the bottom near the beginning, which the player can find by dropping down the cliff at the start. If the player rolls off the ledge to the right of the monitor, bounces off it, bounces off the Spring to the left of the Monitor, then stop and backtrack after passing the Spring to the right, another 1UP Monitor will spawn. The player can repeat this process multiple times to essentially amass an infinite number of lives.

This glitch only exists in the Game Gear version of the game. The smaller screen of the Game Gear, combined with the added momentum, essentially tricks the game into not processing the action. Therefore, the extra life respawns, but the lives counter increases, even though it maxes out at nine on-screen. It cannot happen in the Master System version due to the larger screen size, meaning the player cannot leave the area off-screen fast enough to trick the game.

Not fixed in any version.


Gimmick Mt. Zone

Get the minecart stuck

Sonic2 SMS Bug GMZ MinecartStuck.png

In Act 1, it is possible for the player to get the final minecart stuck on the ramp that it flies off from. Immediately after jumping in, the player must jump out and run after it, then roll to catch up to it. If they get into the minecart on the exact frame that it rolls off the rails, the minecart will become stuck and the player will hear the minecart crash sound. There isn't much the player can do when the minecart is stuck like this, but jumping out of it will cause it to disappear instantly.

Fixed in the Game Gear version.


Crystal Egg Zone

Harmless electrical fields

Sonic2 SMS Bug CEZ HarmlessLightning.png

When fighting the final boss, attacking Eggman when he is charging up the electrical field will cancel the electrical field. If the player attacks him on the exact frame that he starts charging the attack, the electrical field's animation will not be cancelled and the arena will be constantly surging with electricity; however this will not harm the player. This effect lasts until Eggman uses the attack again.

Not fixed in any version.


References


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

Main page
Maps
Comparisons


Manuals
Promotional material
Magazine articles


Development
Hidden content
Bugs
Hacking guide