Knuckles' Chaotix hacking

This page is old, and in the process of being updated while developing for Knuckles Clackers mod,
both for the SonED2 Object Definitions, overall expanded ROMulan support, and Notepad++ UDL files

About SonED2/ROMulan:

Editing Sonic 3 & Knuckles' Angle Island Zone Act

SonED2/ROMulan are game modification utilities created by "Stealth" for the following Sega Genesis games:

  • Sonic 1

  • Sonic 2

  • Sonic 3, Sonic & Knuckles, Sonic 3 & Knuckles

  • Sonic CD

  • Knuckles' Chaotix

The utilities allow the modification and editing of physical level layouts, palettes, graphics, and object placements. This can be done either from a rebuildable disassembly ("disasm") of the game (if applicable), or via a direct binary game edit (using ROMulan code/script injection). More information about the game editing utilities at their official webpage (not mine) at Headcannon (SonED2, ROMulan).

About Knuckles' Chaotix

Knuckles' Chaotix is the only Sonic the Hedgehog-related game released for the poor, underrated, ill-fated Sega 32x add-on for the Sega Genesis. Unlike other Sonic the hedgehog games, this game features many unique and different gameplay and game design mechanics:

  • Knuckles the Echidna as the protagonist

  • 5 other characters (collectively known as the "Chaotix")

  • 5-act zones

  • Buddy-system rubber band 2P co-op system

  • Fully 3D Special and Bonus stages

  • HUB world

  • Time-of-day system

    • Morning

    • Day

    • Sunset

    • Night

  • Sega 32x

  • Much more!

About Knuckle's Chaotix Objdef file:

SonED2 uses object definition files in order to proper display and process the placing of legit game objects. These definition files help show various properties for in-game object layouts:

  • Sprite

    • Question mark ("?") if undefined

    • Appropriate sprite for the object

  • Shows the proper level object placement

  • Tells the user what the proper object bits will do in game

Unfortunately, ROMulan's scripts for Knuckles' Chaotix modification support is relatively new. My object definition files fill in the missing bitfield information and 32x sprites for the game's various objects.

About Notepad++ ROMulan UDL:

Notepad++ is a powerful, programmer-oriented Notepad replacement meant for coding, which allows for

  • Code handling

    • Syntax highlighting

    • Autocomplete

    • Block code/comment folding.

  • Support for various programming languages

    • Common programming languages

    • Less common programming languages via

      • Built-in definitions files

      • UDL (User-Define Language) files.

To make development of Knuckles' Clackers easier for ROMulan support, I created a UDL for ROMulan scripting, which includes syntax highlighting for the ROMulan language keywords and folding for commenting.

Foldable keywords:

    • StartSeg/EndSeg pairs

    • Special UDL block commentary

      • Region @label/EndRegion metacomments

      • Example

        • ;Region @MyRegionLabel
          ;[Insert scripting here for folding]

Sample Notepad++ ROMulan UDL highlighting
(inaudio.txt script; handles Sound Driver data modification)

This is functional, but pre-release.

I plan to have this UDL officially supported/added to Notepad++

How to install Notepad++ UDLs


Updated SonED2 Object listing (with 32x sprites)

Updated in-editor editing (with sprites)
(Notice the path swapper objects and
spring+path swapper object)

Spritesheet with KC enemies

Another spritesheet

SonED2 Objdef Files