Sonic the Hedgehog OmoChao Edition

From Sonic Retro

S1omochao title.png
Sonic the Hedgehog OmoChao Edition
Version: 1.1
Last release: 12th November 2011
System: Sega Mega Drive
Original game: Sonic the Hedgehog (16-bit)

Sonic the Hedgehog OmoChao Edition is a ROM hack of Sonic the Hedgehog (16-bit) by Cinossu.

Originally starting as a joke between himself and Qjimbo, later on becoming a joke hack as an idea for April Fools, with the addition of OmoChao it became a challenge-based (and playable) hack, where the objective is to collect, destroy or even touch as little as possible.

"Hi! I'm OmoChao! I Will Help Guide You As You Play!"

S1omochao omochaoSprite.png
In this ROM hack, the first thing you will notice is that floating behind Sonic, everywhere he goes, is OmoChao. He is there, by his own definition, to help guide you through the game. However, this is not strictly what happens.

OmoChao is there to be more of an annoyance than anything else, as whenever he wishes to say a message the entire game will pause itself until he is finished. This message is also accompanied by a jingle that gets longer, and longer, and longer every time a new message comes up.

Therefore, the only way to truely avoid OmoChao's messages, the jingles, and the waiting around, is to avoid as much of everything as you can!

Can you avoid making OmoChao speak at all?

The Overworld

S1omochao overworld.png
Like the hack Sonic the Hedgehog 1 @ SAGE 2010, the game starts you off on an Overworld with buttons to access each and every level in the game. The difference this time, however, is that there are only the levels available and nothing else.

Starting off, to the right you will encounter Green Hill Zone's mini-hub area, following on to Marble Zone, Spring Yard Zone, and the rest of the game's level sequentially, up until the individual mini-hub area for Final Zone.

The HUD on the Overworld shows the player's Global Score, Global Time and Global Ring Count. While these are not important yet, plans for the future will use this information. Chaos Emerald collection status is also shown just below this information.

Beyond this will appear to be nothing, but after each and every level has been played once (and infinity is not each level's Player Score) a Giant Ring will appear at the end. Jumping into this will lead to the Credits and Final Status Screen.

If you are in a level and wish to return to the Overworld without completing it, pause the game and press the A button.


What makes this hack more than just a joke hack is its challenge-based nature, and as such a ranking system. Each and every level has both a Player Score and a Rank, ranging from RChan eggmanEmblem.pngNothing, RChan bronzeEmblem.pngBronze, RChan silverEmblem.pngSilver, RChan goldEmblem.pngGold and RChan platinumEmblem.pngPerfect. At the end of each level, the Player Score is the number of messages OmoChao has said to you. The Rank is determined based on its Par Message Score, which will be explained below.

Par Message Score

Every level has been played through meticulously to work out the very minimum number of messages that have to be brought up. This is known as the level's Par Message Score, and is used to determine the Rank of the player.

  • To achieve a RChan platinumEmblem.pngPerfect Rank in the level, this is the number of messages (or better, if you can!) you must get as a Player Score.
  • To achieve a RChan goldEmblem.pngGold Rank, you can have up to and including 3 more messages than the score required for RChan platinumEmblem.pngPerfect Rank.
  • To achieve a RChan silverEmblem.pngSilver Rank, you can have up to and including 2 more messages than the score required for RChan goldEmblem.pngGold Rank.
  • To achieve a RChan bronzeEmblem.pngBronze Rank, you can have up to and including 2 more messages than the score required for RChan silverEmblem.pngSilver Rank.
  • Any Player Score beyond the RChan bronzeEmblem.pngBronze Rank limit, and you will recieve RChan eggmanEmblem.pngNo Rank.

A Worked Example: Green Hill Zone Act 1

Green Hill Zone Act 1 has a Par Message Score of 0.

  • For RChan platinumEmblem.pngPerfect Rank: Message count of 0.
  • For RChan goldEmblem.pngGold Rank: Message count ranging from 1 to 3.
  • For RChan silverEmblem.pngSilver Rank: Message count ranging from 4 to 5.
  • For RChan bronzeEmblem.pngBronze Rank: Message count ranging from 6 to 7.
  • For RChan eggmanEmblem.pngNo Rank: Message count greater than 7.

Signs, Shields, Special Stages and Boss Fights

S1omochao ranks1.png
On the Overworld, above the button for each level, is a sign that will tell you both your currently saved Player Score for the level, and both an emblem and the lowest score for the Rank you have achieved. To work out the score required for the next Rank, use the above information. RChan eggmanEmblem.pngNo Rank is indicated by a Dr. Eggman emblem, and will show the score required for a RChan bronzeEmblem.pngBronze Rank anyway.

S1omochao ranks2.png
Similarly, at the end of each level there is a sign that will tell you your Player Score for the level you have just played through, as well as the emblem and lowest score for the Rank you have achieved. RChan eggmanEmblem.pngNo Rank is indicated by your Player Score having a red background, and again the RChan bronzeEmblem.pngBronze Rank score will be shown.

S1omochao shield.png
If you manage to get a RChan bronzeEmblem.pngBronze Rank or better, you will be given a coloured Protective Shield based on your Rank. This Protective Shield will make OmoChao flash, and will prevent him from saying any messages while it is intact. While at the end of a normal level this may seem pointless, you will also recieve a Protective Shield based on your rank before a Boss Fight. This will allow you to damage and defeat the boss without getting hit, and as such keep your Player Score where it is during the battle. Be warned, however, that apart from protecting from OmoChao's messages it is just like a regular shield, and one hit will break it, once again enabling OmoChao's messages.

As well as recieving the Protective Shield, Ranking will make the Giant Ring appear at the end of the level, allowing you access to the Special Stages. You will take the Protective Shield in with you, preventing OmoChao from giving you messages. However, upon contact with the Chaos Emerald or a GOAL Sign, it will break.

Returning to the Overworld after a level without going to the Special Stage will also result in the loss of the Protective Shield.

Temporary OmoChao-Free Areas

S1omochao free.png
In certain levels, you may encounter areas where OmoChao will not be able to tell you messages, and you will be given a Temporary Shield upon entering these. Again, they will break after one hit, so be careful. Once you reach the end of the area, the Temporary Shield will be removed automatically. These areas are shown by a floating OmoChao sign by its entrance.

Final Zone

S1omochao fzsign.png
With Final Zone, Ranking works slightly different, and is based on the Ranks of all the previous levels.

If you do not recieve any messages from OmoChao in Final Zone, your Rank will be the lowest rank achieved of all previous levels. This includes RChan eggmanEmblem.pngNo Rank. If you recieve a message from OmoChao, you will still recieve RChan eggmanEmblem.pngNo Rank regardless of previous levels.

OmoChao's Messages

S1omochao message.png
OmoChao will message you about a number of things, but not absolutely everything. Below a list of everything you want to try and avoid if you want to get as few messages from OmoChao as possible.
  • Collecting Rings
  • Item Monitors (doubly bad, as each individual item inside will also bring up a message)
  • Invincibility Running Out
  • Power Sneakers Running Out
  • Extra Lives
  • Destroying Badniks
  • Bouncing on Springs
  • Stepping on or Pushing Objects on Buttons (doubly bad if an object is on it, as every time you look at it, jump to it, or in general it comes back into view, OmoChao will message you again about it.
  • Getting Hit
  • Getting Killed
  • Drowning
  • Getting Game Over (will also eject you from the level and reset your saved Emerald Count)
  • Getting Time Over (will also eject you from the level)
  • Touching Lamp Posts
  • Getting the Giant Ring (without a protection shield)
  • Finishing the Act (without a protection shield)
  • Finishing the Zone (without a protection shield)
  • Hitting the Boss (without a protection shield)
  • Defeating the Boss (without a protection shield)
  • Getting in that Last Hit (without a protection shield)
  • Collecting a Chaos Emerald
  • Touching a GOAL Sign
  • Getting an SRAM error (if you get an SRAM error, or if you disable SRAM in the emulator you are playing it one, Omochao will display the message at startup)
  • Getting the ROM checksum error (if the calculated checksum doesn't match the one in address $18E in ROM file, Omochao will display the message at startup, the jingle won't stop until you press Start.png button)

Accompanying each message is a short jingle, and during the time this is playing gameplay will pause until it is over. After each new message, this short jingle will get longer, and longer, and longer, so be sure to avoid as much as possible!

Losing a life will not reset OmoChao's message jingle length. Only by completing (or otherwise exiting) the level will this happen.

(There is a hidden message from OmoChao after 100 messages have appeared.)

Credits and Final Status Screen

Once you have played every level at least once, a Giant Ring will appear at the end of the Overworld, allowing you access to the Credits. Once these have all rolled through, you will see the Final Status Screen with Dr. Eggman on it.

If you have missed any Chaos Emeralds, he will be juggling the ones you are missing.

If you have any level Ranks other than RChan platinumEmblem.pngPerfect, he will be juggling the ones you need for a Perfect Score throughout the game.

If you have achieved a Perfect Score, congratulations! You will see Dr. Eggman jumping up and down furiously on an "End" sign. You will also know you have achieved a Perfect Score by the music on both the Overworld and Credits being slightly altered.

Future Plans

Future plans for this hack include adding additional levels to the game, as well as implementing Retro Channel into it, allowing players to share their results. A soon to be added feature is with SonMP3, to give OmoChao a voice, as noted in the Credits.


Download.svg Download Sonic the Hedgehog OmoChao Edition
File: (599 kB) (info)
Current version: 1.1
  • Alternate Version (info) (599 kB) (599 KB) - The message jingle will always increase in pitch, never going back down. (WARNING: Painful on the ears when it gets too high!!)

Version History

  • v1.1 - Fixed major bug that wouldn't let people get their shield in Final Zone nor get to the Credits
  • v1.0 - Initial release

Gameplay Videos

Introduction to the Game and the Basic Premise

Green Hill Zone Act 1 Perfect Rank Run

External Links

Sonic Retro
Release thread
at Sonic Retro