Silksong Android

Silksong Android

Hollow Knight: Silksong Android port with dual-screen capabilites and optional Steam integration for game files and cloud saves.

Thanks to Kaz Kirigiri for artwork and design sketches!

Features

• Dual screen: Full implementation of the in-game menu for dual screen devices. Show map, use items, change your crest and more
• Steam integration (optional): Sign in to Steam if you want the app to download game files and/or your Steam cloud saves for you
• High performance: Compiles to native arm64 via IL2CPP and uses Vulkan shaders
• Fully open source and legal: Supply your own game files either manually or through Steam sign-in (the app downloads them for you)
• Compilation on device: Download the APK and supply the game files, porting happens on device (20–30 min on Snapdragon 8 Gen 2)
• Mod support (beta): BepInEx 5 plugin support (see Mod support)
• QoL settings: Skip intro, set resolution, auto upload/download cloud saves etc.
• Any device: Any Android device works, single screen as well.

Setup

1. Download the latest APK from Releases and install it.
2. Supply your own game files. Either copy them across from your PC yourself, or let the app fetch them for you by signing in to Steam.
3. Press the button. The app fetches everything it needs and builds the game. The build takes 20–30 minutes on a Snapdragon 8 Gen 2.
4. Play!

Any device should do (tested on the AYN Thor and the Retroid Pocket Flip 2). Open an issue if your device doesn't work.

Supplying the game files yourself

If you'd rather not sign in, download the game's Linux depot on a PC with DepotDownloader. The Linux files are the ones the port is built from; the Windows (1030301) and macOS (1030302) depots will not do, and the app rejects them:

DepotDownloader -app 1030300 -depot 1030303 -username <your account> -password <your password> -dir silksong

Copy the whole silksong folder onto the device, as long as it is on the device's own storage. Then press Choose folder in the app and pick it.

silksong/                          <-- pick THIS one
├── Hollow Knight Silksong.x86_64
├── UnityPlayer.so
└── Hollow Knight Silksong_Data/
    ├── Managed/
    ├── MonoBleedingEdge/
    ├── Plugins/
    ├── Resources/
    ├── StreamingAssets/
    ├── globalgamemanagers
    ├── resources.assets
    └── ...

Wherever you put them, leave them there. The game is several gigabytes of content that is never copied into the app: it is read from that folder every time you play, and every app update that rebuilds the game reads it too. Deleting or moving the folder stops the game from starting. The app leaves a SILKSONG-DO-NOT-DELETE.txt in there saying so.

Mod support (beta)

BepInEx 5 plugins work, with one catch: since the games compiles to C++ code to get maximum performance, mods need to be compiled too, so installing or removing a mod means rebuilding. You can still enable/disable mods without rebuilding.

1. Open Mods from the launcher and press Install a mod from a folder. Pick the folder the mod came in — the whole folder is copied in, so a mod that is a plugin plus its own libraries and config needs no sorting out.
2. Say yes when it offers to rebuild, or carry on and rebuild later.
3. Config files appear in mods/config after the first launch.

The Mods screen lists everything it found, marks each one built or not built, and says how many patches it applied and every one it could not. The rebuild is incremental, so installing a new mod should not take long.

What does not work: transpilers, patch targets computed at runtime, Reflection.Emit, and loading a DLL discovered at runtime. There is no IL left by the time the game runs, so nothing can be patched then. The mods screen names every patch a plugin could not apply, before the build starts. Plugins with definite missing APIs or required dependencies are marked failed and left out, rather than breaking compilation for the other mods.

The configuration menu

Mods that expose settings expect BepInEx's Configuration Manager to be there to draw them. Install it the same way as any other mod.

Open it with L3+R3. That binding lives in mods/config/BepInEx.cfg and because it is a BepInEx setting like any other, the menu lists it, under Advanced settings.

Tested mods

Built and played on device. Links go to the page each was downloaded from.

• BepInEx 5 + Configuration Manager (only needed for configuration menu)
• AutoMap
• SaveScopedConfig (required by AutoMap)
• Bonfire Teleport (use the normal in-game map to teleport)
• Stakes of Marika – Rebirth Anywhere (partial, no custom spawnpoint)
• Healthbar & Damage Show

If a mod is not working for you, feel free to open an issue, but I cannot guarantee that all mods will be supported.

Steam Cloud Saves

If you sign in to Steam, you also get your Steam Cloud saves. Pull before you play, push when you're done, or let the launcher do both automatically (see settings). Save conflicts are handled, but back your saves up if you want to be certain nothing is lost.

Signing in, by QR code or password, goes through JavaSteam, an open-source Steam client library. Your password is never stored: the only thing kept is the login token Steam issues in return, encrypted, and it never leaves the device.

AI assistance

Much of this project was written with AI assistance. Everything in it is reviewed and tested on real hardware before release.

Legal

This repository and the APK contain no game content and nothing Unity-made. Silksong is © Team Cherry, and none of its code, art or audio is distributed here. The APK is a build system: it downloads Unity's toolchain, takes your game files, and compiles a playable build on your own device.

The tooling is MIT-licensed; see LICENSE. Third-party open-source components shipped in the APK are listed in NOTICE.md, which also records what the APK deliberately does not contain.

Building from source

You don't need Unity or any game files to build the APK:

make player     # once: fetch Unity's Android player module (~642 MB)
make surgery    # once: build bundle-surgery
make dev        # rebuild, repackage, install

Requires an Android SDK, JDK 17+ and the .NET 8 SDK; on Windows use Git Bash. make docker-apk does the same in a container. See COPILOT.md for the full development loop.