HK4E Sophon Downloader

A tool to download anime game assets using their new Sophon-based download system.

Starting from version 5.6, they transitioned to using Sophon Chunks for updates and discontinued distributing ZIP files. As a result, it is no longer possible to download game assets without using their Launcher. This tool aims to bypass that limitation, so you can download directly, efficiently, and without bloat.

Features

• Full and Update download modes
• Uses official API (getBuild, getUrl, etc.)
• Language/region selector
• Built-in auto validation via real-time API
• Fast, parallel downloads (multi-threaded)
• Zero dependencies

Requirements

• Install .NET 9.0 SDK

Compile Instructions

To compile the project:

1. Just click compile.bat
2. The release output automatically will be in the bin folder

How to Use

Option 1: Interactive Menu (Recommended)

Just click Sophon.Downloader.exe You’ll be greeted with:

=== Sophon Downloader ===

[1] Full Download
[2] Update Download
[0] Exit

Navigate with number keys, follow the prompts, and you're good.
It will auto-detect language options and available versions from your config.

Option 2: CLI Mode (Advanced Users)

Sophon.Downloader.exe full   <gameId> <package> <version> <outputDir> [options]
Sophon.Downloader.exe update <gameId> <package> <fromVer> <toVer> <outputDir> [options]

Example:

Sophon.Downloader.exe full gopR6Cufr3 game 5.7 Downloads
Sophon.Downloader.exe update gopR6Cufr3 en-us 5.6 5.7 Downloads --threads=4 --handles=128

CLI Options

Option	Description
--region=...	OSREL or CNREL (default: OSREL)
--branch=...	Branch override (default: main)
--launcherId=...	Launcher ID override
--platApp=...	Platform App ID override
--threads=...	Number of threads (auto-limited)
--handles=...	Max HTTP handles (default 128)
--silent	Disable all console output except errors
-h, --help	Show help info

If your input is garbage, it will fall back to defaults silently.
You were warned.

config.json

This file is auto-generated if not found. You can customize the default region and add more versions.

Example:

{
  "Region": "OSREL",
  "Branch": "main",
  "LauncherId": "VYTpXlbWo8",
  "PlatApp": "ddxf6vlr1reo",
  "Threads": 4,
  "MaxHttpHandle": 128,
  "Silent": false,
  "Versions": {
    "full": ["5.6", "5.7", "5.8"],
    "update": [
      ["5.5", "5.6"],
      ["5.5", "5.7"],
      ["5.6", "5.7"],
      ["5.6", "5.8"],
      ["5.7", "5.8"]
    ]
  }
}

Notes

• If you mess up the config, the app will silently fallback to default values.
• Garbage values like "Silent": lmao or "Threads": 99999 Silently fixed automatically.
• Version/tag values are validated live via the API, not by regex. If your version doesn't exist, you'll get a clean [ERROR] Failed to fetch manifest — no crash.
• Maximum thread count = your CPU core count.

Disclaimer

This tool is for reverse engineering & educational use only.
Not affiliated with miHoYo, Cognosphere, or any official entity.
Do not use this project for public distribution or commercial purposes.