Split-screen on PC

Synergy

Up to 8 players on one PC, with controllers, keyboard and mouse or several keyboards and mice.

8Verified handler

Handler “Synergy” by dr.oldboi, version 2

P4+4 more players

What works

With Nucleus Co-op, up to 8 players can play Synergy together on one PC, each in their own part of the screen, with controllers, keyboard and mouse or several keyboards and mice. The free community handler “Synergy” by dr.oldboi does the setup and was checked by hub moderators: version 2, updated 12 Jan 2023. Synergy is a shooter and platformer game from 2005.

Players8
ControllersSupported
Keyboard and mouseSupported
Several keyboards and miceOne per player
Hub moderatorsVerified

How to play Synergy split screen on PC

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
Install the Synergy handler
In Nucleus Co-op, search the Hub for Synergy and install its handler, or download the handler file from this page and drop it on the Nucleus window. Then show Nucleus where Synergy is installed.
Download the handler file (.nc)
Take a seat
Each player presses a button on their own controller to join 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.
Launch and connect
Press Launch: Nucleus opens one copy of Synergy 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
Synergy 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 controller per player, or one keyboard and mouse per player. Controllers · Keyboards and mice
A PC that can run 8 copies
Each player runs their own copy of Synergy, 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

Create a LAN server in one instance and connect in the others with the find server option/LAN tab, pause in the hosting instance when joining so you can use the cursor to join in the other instances.

If you can not connect the instances in latest version of the game try downgrading Half Life 2 and Synergy to the previous working version by right clicking the game in Steam, properties, then to the betas participation tab.

Enable gamepad in the game options/mouse tab for gamepad instances, make sure Steam input is disabled in this game via Steam for the gamepads to restrict correctly: https://steamcommunity.com/discussions/forum/1/135512931356432928/

If you use keyboards and mice after all the instances have launched, resized and positioned correctly, press the END key once to lock the input for all instances to have their own working cursor and keyboard, you need to left click each mouse to make the emulated cursors appear after locking the input, press the Escape key in your respective keyboard after locking the input if the camera movement is not working correctly. Press the END key again to unlock the input when you finish playing. You can also use CTRL+Q to close Nucleus and all its instances when the input is unlocked.

This handler launches all instances using your Steam account so Steam needs to be opened.

Authors and Contributors of this handler: dr.oldboi and Talos91 from the Split Screen Dreams Discord.

About Synergy

Synergy is a simple Half-Life 2 Modification (Mod) that enables you to play through the Half-Life 2 series and many other 3rd-party campaigns cooperatively with friends

Summary from IGDB