by Emerald Mentality in

Sonic and the Mystic Gems

Creator: Eduardo Knuckles and Harder Project
Classification: ROM Hack
Base Game: Sonic the Hedgehog 1


Sonic And The Mystic Gems (previously known as Sonic 1 Harder Levels) is a hack made by Eduardo Knuckles and his team Harder Project of Sonic the Hedgehog on the Sega Mega Drive. It began in 2005 with the simple purpose of being a generic Sonic 1 for Sega Genesis with increase difficulty and revamped versions of the original levels. But now, it’s going to present a completely new gaming experience with a new style of level layouts full of paths everywhere among new enemies, new objects, new character abilities, new menus, completely different styles of the Sonic 1 special stages and much more!

This time, the Sonic 1 original zones gave place to new zones with unique art and a different pleasure to the eyes. The music is also being reformed to give a better ear-hearing experience, now less amateur and more like what a Sonic game must be.

Characters can glide, climb, fly, swim and homing attack everywhere but at the same time these are their generic abilities; they work slightly different to make the levels more explorative and fun to play. Smashing blocks, smashing ceilings, smashing walls and smashing enemies is what will make you positively shocked with how the game has absolutely nothing to do with its predecessor “Sonic 1 Harder Levels”.

Gameplay now focuses in the new “characters alternation” gameplay methodology, so to proceed in the game you’ll need to know each behavior from each of the three characters available on it if you don’t want to be completely stuck or lost into the mazes of the game’s explorative sections. Changes to the game include layouts, sprite mappings, new levels, a fixed engine, new sound effects and new music. The game also features some Master System features.


Unsatisfied by his last defeat, Robotnik sought for other methods to kick Sonic off his way. While he was looking for the Chaos Emeralds, he found another source of energy which seems to be powerful like those emeralds. This source of power is known as Mystic Gems. As opposite of the chaos emeralds, they have an destructive evil power. If he gets access to these gems he can rule the world. Sonic, Tails and Knuckles now have to prevent Robotnik from find this evil power, so there’s how this new adventure begins. There’s a expert plan to take over South Island with robots and courses, but Sonic and his friends will not let the doctor to conclude it easily.


  1. New splash screens
  2. Sonic, Tails and Knuckles have levels made according to the usage of their modified abilities.
  3. An Options menu where difficulty, character and playlist can be chosen as long as the new Music Theater can be accessed
  4. Game mode select (Original Mode and Harder Mode)
  5. Game soundtrack (Mystic Gems Originals, Dj. Joker27 Customs, Retro Style and a Random Playlist based on songs from each playlist)
  6. Initial Character Select (Sonic, Tails And Knuckles)
  7. Music theater that shows notes and music names and give the option to enable or disable channels to interact with them
  8. New title screen
  9. A save data selection screen (that was cut from the current demo)
  10. And more. A lot more!

Important Note

Although the game is about to show a different gaming experience, it should be borne in mind that the current version is in an alpha prototype state and a lot will be modified until the next versions are released in the future.

Many objects, screens and cutscenes are currently under development and may have been cut from this demo; and that includes enemies, bosses, badniks, new mechanics and even stages. Currently only a total of 5 acts and special stages are available to play. The project is not being developed quickly, so be patient and understand that a lot will be improved over time. However, we at Harder Project are open to constructive suggestions and comments that will surely help us in the evolution of the project.

Credits & Special Thanks

  1. Mistergambit for his Spring Yard Zone and Labyrinth Zone level art used in the game.
  2. Tweaker for his information regarding music importing, bug fixes and the speedcap removal.
  3. HPZMan for the new sound driver instruments and the dynamic tile-set system.
  4. Selbi for some new exclusive ASM things and improvements.
  5. Master3k for sending and fixing some music.
  6. nineko for creating the xm3smps tool which was essential for the creation of some songs. Special credits to him for the different songs per act system used.
  7. SCAA for their art.
  8. Puto for his tutorial to add Spin Dash.
  9. FraGag for his tutorial to fix the spike bug.
  10. SonicVaan for beta testing.
  11. HCKTROX for the lead programming and bug fixing.
  12. GenesisFan64 for the save screen menu, for some fixes related to the fade-out and others.
  13. MarkeyJester for lots of important code and a whole load of others.
  14. Irixion for beta testing.
  15. PsychoSk8r for his the dynamic palettes tutorial.
  16. Esrael for fixing essential things in the new sound driver.
  17. Prilix Bõkun for bug searching and beta-testing
  18. Estlib for various art stuff related to levels and for additional help with creation of gimmicks and objects
  19. DJ. Joker27 for his very big importance in specific level and misc music
  20. Mighty Arnold for additional support with beta-testing and level layout design

Kenny0989 for additional support in the music department Special credits to Harder Project’s Team by all the useful exclusively things used in the project.

Sonic Metropolis Credits

  1.  Eduardo Knuckles and Harder Project for the ROM Hack and its information
  2. Sonic Retro for displaying information on the ROM hack
  3. YOU for supporting Sonic Metropolis

All information shown is credited to Eduardo Knuckles and Harder Project as well as Sonic Retro.

0 0 votes
Post Rating
Notify of
Inline Feedbacks
View all comments