This software allows you to modify "The Legend of Zelda: A Link to the Past" (US or JP) ROMs. It is built for compatibility with ZScream projects and designed to be cross-platform.

Quick Start

Download the latest release for your platform from the releases page.
Load ROM via File > Open ROM.
Select an Editor from the main toolbar (e.g., Overworld, Dungeon, Graphics).
Make Changes and save your project.

General Tips

Experiment Flags: Enable or disable new features in File > Options > Experiment Flags.
Backup Files: Enabled by default. Each save creates a timestamped backup of your ROM.
Extensions: Load custom tools via the Extensions menu (C library and Python module support is planned).

Feature Status

Feature	State	Notes
Overworld Editor	Stable	Supports vanilla and ZSCustomOverworld v2/v3 projects.
Dungeon Editor	Experimental	Requires extensive manual testing before production use.
Tile16 Editor	Experimental	Palette and tile workflows are still being tuned.
Palette Editor	Stable	Reference implementation for palette utilities.
Graphics Editor	Experimental	Rendering pipeline under active refactor.
Sprite Editor	Experimental	Card/UI patterns mid-migration.
Message Editor	Stable	Re-test after recent palette fixes.
Hex Editor	Stable	Direct ROM editing utility.
Asar Patching	Stable	Wraps the bundled Asar assembler.

Command-Line Interface (<tt>z3ed</tt>)

z3ed provides scripted access to the same ROM editors.

AI Agent Chat

Chat with an AI to perform edits using natural language.

# Start an interactive chat session with the AI agent

z3ed agent chat --rom zelda3.sfc

‍Prompt: "What sprites are in dungeon 2?"

Resource Inspection

Directly query ROM data.

# List all sprites in the Eastern Palace (dungeon 2)
z3ed dungeon list-sprites --rom zelda3.sfc --dungeon 2
 
# Get information about a specific overworld map area
z3ed overworld describe-map --rom zelda3.sfc --map 80

Patching

Apply assembly patches using the integrated Asar assembler.

# Apply an assembly patch to the ROM

z3ed asar patch.asm --rom zelda3.sfc

Extending Functionality

YAZE exports a C API that is still evolving. Treat it as experimental and expect breaking changes while the plugin system is built out.