Black Mesa

What works

With Nucleus Co-op, up to 32 players can play Black Mesa together on one PC, each in their own part of the screen, with keyboard and mouse or several keyboards and mice. The free community handler “Black Mesa” by dr.oldboi does the setup and was checked by hub moderators: version 2, updated 28 Sept 2024. Black Mesa is a shooter, platformer and adventure game from 2020.

• Players32
• ControllersNot supported
• Keyboard and mouseSupported
• Several keyboards and miceOne per player
• Hub moderatorsVerified

How to play Black Mesa split screen on PC

1. Get Nucleus Co-op

   Download Nucleus Co-op, free for Windows 10 and 11, and unzip it into its own folder, for example C:\NucleusCo-op. There is no installer.

   Keep it out of Program Files, your user folder and OneDrive.

   Download Nucleus Co-op

2. Install the Black Mesa handler

   In Nucleus Co-op, search the Hub for Black Mesa and install its handler, or download the handler file from this page and drop it on the Nucleus window. Then show Nucleus where Black Mesa is installed.

   Download the handler file (.nc)

3. Take a seat

   Each player joins with their own keyboard and mouse and takes a spot on the screen. Pick a layout that fits your players.

   Playing with several keyboards and mice? Press End once everything is in place to give each window its own cursor.

4. Launch and connect

   Press Launch: Nucleus opens one copy of Black Mesa per player and lays the windows out on your screen. Then link them in game, usually one player hosts a LAN or online session and the others join it. The handler notes say how.

What you need

• A Windows 10 or 11 PC

  Nucleus Co-op runs on Windows only. System requirements

• Black Mesa for Windows

  Installed on that PC. Nucleus starts every player's window from that one install.

• Nucleus Co-op, free

  With .NET Framework 4.7.2 or later and the Visual C++ 2015–2022 runtimes (x86 and x64). Download

• Something to play with

  One keyboard and mouse per player. Controllers · Keyboards and mice

• A PC that can run 32 copies

  Each player runs their own copy of Black Mesa, so the PC carries several times the usual load. Lower the graphics settings if it struggles. Performance tips

• A multiplayer mode

  Nucleus links the windows through the game's own LAN or online mode; the handler takes care of it.

Handler notes

Black Mesa screenshots