Split-screen on PC

Ultrakill

Up to 5 players on one PC, with controllers or keyboard and mouse.

5Verified handler

Handler “Ultrakill Jacket/Polarite MP mod” by birden, version 2

P4+1 more players

What works

With Nucleus Co-op, up to 5 players can play Ultrakill together on one PC, each in their own part of the screen, with controllers or keyboard and mouse. The free community handler “Ultrakill Jacket/Polarite MP mod” by birden does the setup and was checked by hub moderators: version 2, updated 9 Mar 2026. Ultrakill is a shooter, platformer and indie game from 2020.

Players5
ControllersSupported
Keyboard and mouseSupported
Several keyboards and miceNot supported
Hub moderatorsVerified

How to play Ultrakill 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 Ultrakill handler
In Nucleus Co-op, search the Hub for Ultrakill and install its handler, or download the handler file from this page and drop it on the Nucleus window. Then show Nucleus where Ultrakill 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.
Launch and connect
Press Launch: Nucleus opens one copy of Ultrakill 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
Ultrakill 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; one player can use the keyboard and mouse. Controllers
A PC that can run 5 copies
Each player runs their own copy of Ultrakill, 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

Video tutorial/showcasing the handler: https://www.youtube.com/watch?v=KzKFIallEPE

IMPORTANT: You need to have the Jaket multiplayer mod OR Polarite MP mod installed and ALREADY WORKING in your game files using MANUAL INSTALLATION.

These mods are mostly only working on older builds of the game, so downgrade your game on steam and install them.

If you want your main game save in nucleus copy the Saves folder in your main game > go into nucleus right click ULTRAKILL > Open content folder > open the instance folder you want to have your main game save and paste the folder there.

One keyboard/mouse and controllers working

About Ultrakill

Ultrakill is a fast-paced ultraviolent retro FPS combining the skill-based scoring from character action games with unadulterated carnage inspired by the best shooters of the 90's. Rip apart your foes with varied destructive weapons and shower in their blood to regain your health.

Summary from IGDB