Hytale Client Mod

This repository serves as a practical example for Hytale Client modding and reverse engineering. It provides a workflow to bypass the challenges of Native AOT compilation and start coding your own modifications.

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Reverse Engineering the Hytale Client

The Hytale client is compiled using Native AOT.
Most of the game logic is located inside HytaleClient.dll, which was originally written in C#.

The Challenge

The main difficulty is making the loaded DLL’s C# logic visible again.

• IDA Pro currently cannot properly decompile Native AOT binaries (and there is no reliable plugin for this).
• Tools like dnSpy also do not work for Native AOT.

The Solution

A working reconstruction workflow:

• Scylla → dump and rebuild imports
• Ghidra → analyze the dumped binary
• Native AOT Ghidra Plugin → reconstruct managed structures

This does not restore everything, but it gives a very strong base for analysis.

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1. Dumping the Client (Scylla)

To analyze the binary, we first need to extract a "clean" version from memory and fix the Import Address Table (IAT).

1. Launch Hytale: The process must be running.
2. Open Scylla: Run Scylla_x64.exe (Download here).
3. Attach: Select the HytaleClient.exe process.
4. Search IAT: Click IAT Autosearch and confirm.
5. Get Imports: Click the Get Imports button.
6. Dump:
   • Click Dump and save it as HytaleClient_dump.exe.
   • Click Fix Dump, select the HytaleClient_dump.exe you just created.
   • This will generate HytaleClient_dump_SCY.exe.

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2. Reverse Engineering (Ghidra)

To make the native code readable again, we use Ghidra with a specific Native AOT plugin.

1. Install Plugin: Download the Native AOT Analyzer.
2. Setup Ghidra:
   • Open Ghidra.
   • Go to File -> Install Extensions.
   • Select the NativeAOT Zip file and restart Ghidra.
3. Analysis:
   • Import HytaleClient_dump_SCY.exe into a new project.
   • When prompted for analysis, ensure Native AOT Analyzer is selected (this is crucial).
   • Wait for the analysis to complete (this may take several minutes).

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3. Development Setup (CMake)

It is mandatory to build your mod DLL in Release mode for it to work correctly.

• IDE: Visual Studio Code with the CMake Extension.
• Compiler: MSVC 2022/2026 x64 (Release).
• Usage: Open the project in VS Code. The CMake extension should detect the project automatically. Simply select the MSVC x64 Release kit and build.

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4. Injector

The project includes a simple Python-based injector using the PyMem library.

Installation:

pip install -r requirements.txt

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License

This project is licensed under the Apache License 2.0.
You are free to use, modify, and distribute this software under the terms of the license.