Grasscutter

A WIP server emulator for Genshin Impact 2.3-2.6

Note: For support please join the Discord server.

Current features

• Logging in
• Spawning monsters via console
• Combat
• Inventory features (recieving items/characters, upgrading items/characters, etc)
• Co-op does work, but movement is kind of buggy and some player ults do not spawn properly
• Friends list
• Gacha system

Running the server and client

Prerequisites

• JDK-8u202 (mirror link since Oracle required an account to download old builds)
• Mongodb (recommended 4.0+)
• Proxy daemon: mitmproxy (mitmdump, recommended), Fiddler Classic, etc.

Starting up the server (Assuming you are on Windows)

1. Setup compile environment gradlew.bat
2. Compile the server with gradlew jar
3. Create a folder named resources in your server directory, you will need to copy BinOutput, ExcelBinOutput folders and TextMap*.json which you can get from a repo like https://github.com/Dimbreath/GenshinData into your resources folder.
4. Run the server with java -jar grasscutter.jar. Make sure mongodb is running as well.

Connecting with the client

½. Create an account using command below

1. Run a proxy daemon:
   • mitmdump: mitmdump -s proxy.py --ssl-insecure
   • Fiddler Classic: Run Fiddler Classic, turn on Decrypt https traffic in setting and change the default port there (Tools -> Options -> Connections) to anything other than 8888, load this script.
   • hosts: Redirect at least api-account-os.hoyoverse.com and dispatchosglobal.yuanshen.com to your dispatch server ip.
2. Trust CA certificate:
   • mitmdump: certutil -addstore root %USERPROFILE%\.mitmproxy\mitmproxy-ca-cert.cer
3. Set network proxy to 127.0.0.1:8080 or the proxy port you specified.
4. yoink

• or you can use run.cmd to start Server & Proxy daemon with one click

Server console commands

account create [username] {playerid} - Creates an account with the specified username and the in-game uid for that account. The playerid parameter is optional and will be auto generated if not set.

In-Game commands

There is a dummy user named "Server" in every player's friends list that you can message to use commands. Commands also work in other chat rooms, such as private/team chats.

!spawn [monster id] [level] [amount]

!give [item id] [amount]

!drop [item id] [amount]

!killall

!godmode - Prevents you from taking damage

!resetconst - Resets the constellation level on your current active character, will need to relog after using the command to see any changes.

!sethp [hp]

!clearartifacts - Deletes all unequipped and unlocked level 0 artifacts, including yellow rarity ones from your inventory

Quick Troubleshooting

• If compiling wasnt successful, please check your JDK installation (must be JDK 8 and JDK's bin PATH variable is correct)
• My client doesn't connect, doesn't login, 4206, etc... - Mostly your fiddler is the issue, make sure it running on another port except 8888
• Startup sequence: Mongodb > The server > Proxy daemon (mitmdump, fiddler, etc.) > Client
• If 4206 error constantly prompt up, try to use jdk-8u202-b08 instead of other versions of JDK