SonED2 boasts the following features:

Data Support:

Currently, SonED2 officially supports the following game data:

Sonic the Hedgehog - Tiles, Palettes, Level Layout, Object Layout, Special Stages
Sonic the Hedgehog 2 - Tiles, Palettes, Level Layout, Object Layout
Sonic the Hedgehog 3 - Tiles, Palettes, Level Layout, Object Layout, Bonus Stage
Sonic & Knuckles - Tiles, Palettes, Level Layout, Object Layout, Bonus Stages
Sonic the Hedgehog CD - Tiles, Palettes, Level Layout, Object Layout
"Sonic Crackers" - Tiles, Palettes, Level Layout, Object Layout
Knuckles' Chaotix - Tiles, Palettes, Level Layout, Object Layout


SonED2 contains several editors for the various supported data types, which are described in more detail in in the screenshots section to the right. Each description also includes a link to a relevant portion of the documentation

ROMulan Integration

The built-in ROMulan functionality automates the processes of obtaining game data for editing and inserting the edited data back into the game. The download package comes with premade ROMulan extract/inject scripts for the above-mentioned games

Object Listing Files

Editing modes that deal with any type of "Object" will call on a modifiable "Object Listing File" that will give the editor information on how to draw the Object, and when applicable, how its properties can be edited:

- Standard Objects Listing Files
- Sonic 1 Special Stage Objects Listing Files

The download package comes with premade Object Def Files for the above-listed games, which contain varying-amounts of pre-defined Objects. These files are stored with the above-mentioned Project Files

Tile/Level/Palette Import from Image

 Palette colors, Level Layout sections, and all three Tile stages may be imported from PCX or TGA images, allowing for the creation of levels and their graphics in external programs. This process will detect duplicate graphics and graphics that have been flipped/mirrored in order to reduce the total number of tiles used. 

Sonic 2 Competition Mode Compatibility

Sonic the Hedgehog 2 uses a special graphics mode of the Megadrive/Genesis to achieve a split-screen playmode. This mode imposes additional requirements on the tile data for correct display. SonED2 is capable of converting tilesets to conform to some of these rules, while others are cosmetic and cannot be accounted for by any automated system

Image Import

The "Export to Image" menu contains features for outputting TGA images containing of various editable data, such as Tileset and Solidity lists, complete Level Layouts with Object and/or Solidity overlays, and Special Stage maps

HCGE Export

HCGE is a versatile, multiplatform 2D game engine. The "Convert for HCGE" menu contains features to reproduce the currently-loaded Tile graphics, solidity, and Level Layout as HCGE-format Tile and Level data files, for use in games created for HCGE


DOWNLOADSystem Requirements:
386x or better processor
16megs or more RAM
Win95 or later with DirectX7 or later

Overview and Documentation

SonED2 is a data editor supporting the 2D Sonic the Hedgehog series of games for the Sega Megadrive/Genesis and its accessory hardware, and any games that may share common data formats.

Full documentation for editor usage and supporting file formats is included with the download package and is also available on this site. The sections below provide links to relevant texts, and the "ReadMe" document is provided as an overview and entrypoint.


Below is a list of SonED2's editing modes:

Level Editor

Within the level editor, place the 128x128 or 256x256 Chunks/Metatiles to create the level layout. Also available for viewing at the same time are the Object Layout (on by default, can be toggled off), and level solidity overlays for both available "paths" (off by default, can be toggled on)

The Object Editor can be used to move Objects around the level, change their properties, remove existing Objects from the level, and add new Objects to the level. The Object Listing Files allow information to be given to SonED2 that allow it to draw Objects with proper graphics, and present their properties for editing in a coherent way. Also available for viewing in this editor are the same level solidity overlays as in the Level Editor

The Tile Editor actually contains five separate editing sections- Edit graphics and properties for 8x8 Tiles, 16x16 Blocks, and 128x128 or 256x256 Chunks/Metatiles, as well as level solidity height maps and palettes. Other features include viewing solidity overlay in the Chunk editor, viewing Block underlay on the solidity height map editor, creating an "alpha blend" palette for an "underwater" effect, and using the "Tile Selector" area to view and select Tiles, Blocks, Chunks and solidity from their respective set listings and to manage those listings with functions such as append, insert, delete, etc, all while respecting separate pages of a set (when applicable)

With the Sonic 1 Special Stage Editor, modify or create maps for the Sonic 1 Rotating Special Stage, or for the similar Rotating Slot Bonus Stage in Sonic & Knuckles. For each "Object" type that makes up the map, Sonic 1 Special Stage Object Listing Files provide this editor with graphics, a brief description, and even information to animate the graphic within the editor, which is especially helpful in the creation coherently-animated wall patterns


16.04.29 "Quick & Dirty"
(Quickly put together while otherwise busy; please excuse any remaining glitches)
- Level/Object and Tile editor usability updates- separate, resizeable windows with 5 zoom levels
- Feature to edit chunk collision types from within Level editor
- Mouse Wheel Support

- Loading nonexistent files now properly resets the number of tile/block/chunk pages
- The "Remember Sprite State" is now correctly set when using Sonic 2 Objects type without a separate Rings List
- Fixed an occasional crash when attempting to import 16x16 blocks or larger structures