UKButt Ultrakill Mod Step By Step Install and Customization Instructions


The Full Arsenal update caused some breakage with older versions. UKButt v1.4 is out now, it is recommended to update to that to fix issues. The instructions here have been updated to point to the new release.

To update from < v1.3, rerun the mod installation steps starting at step 7

Other places to look for help if these instructions don’t work

Mod Installation and Verification

This guide will assume you’re on Windows 10+ and using Steam.

  1. Install Ultrakill through Steam.

  2. Install Intiface Central - Intiface® Central | Intiface®

  3. Download BepInEx v5
    a. The latest version as of this writing is available here: Release BepInEx 5.4.21 · BepInEx/BepInEx · GitHub
    b. YOU MOST LIKELY WANT THE X64 VERSION. You do not want Unix or x86 unless you know what you are doing, and if you know what you are doing why are you reading this tutorial.
    b. If there is a newer version, please reply to this and let me know so I can update.

  4. You will need to unzip BepInEx into your Ultrakill install directory.
    a. For most users, this will be c:\Program Files (x86)\Steam\steamapps\common\ULTRAKILL

  5. For things to work, after you unzip you should see:
    a. A file named winhttp.dll in the ULTRAKILL directory
    b. A directory named BepInEx in the ULTRAKILL directory

  6. Run Ultrakill once. You can basically just open and close it. Afterward, you should see a Plugins directory in the BepInEx directory in your Ultrakill install.

  1. Download UKButt
    a. Latest version will be at Release Update 1.4.0 · PITR-DEV/ukbutt-mod · GitHub
    b. Download the file called UKButt.[version].zip
    c. You do not need the Source Code files.

  2. Unzip UKButt and put the contents in c:\Program Files (x86)\Steam\steamapps\common\ULTRAKILL\BepInEx\Plugins

  3. After this step, there should be 5 files in c:\Program Files (x86)\Steam\steamapps\common\ULTRAKILL\BepInEx\Plugins
    a. ButtplugManaged.dll
    b. NewtonsoftJson.dll
    c. UKButt.dll
    d. websocket-sharp.dll

  4. If those files are not there, the mod may not work, so check to make sure they exist. (IGNORE THE LICENSE FILE IN THE IMAGE, it is not needed.)

  5. Start Intiface Central, and hit the Server Start button, which is the Play button on the top left corner.

  6. If you want to test your device before using UKButt, go to the Devices tab, and hit “start scanning”. Intiface Central should find your device, and will allow you to test it before hooking up UKButt.

  7. Once you are ready to play Ultrakill with the UKButt mod, start Ultrakill.

  8. If you alt-tab to Intiface Central, you should see that Ultrakill as connected. This will be shown on the client status portion of the control panel, like so:

  9. Once the game is connected, it will be in Varied Mode. If you start the game, there should be vibrations on firing, sliding, and other actions/events.

Customizing the Mod

UKButt comes with a set of preferences that can be changed to modify the behavior of the mod. These preferences are listed in the UKButt README

To change customizations.

  1. The game must be in cheat mode. Start the game, enter a level, and hit: Up, Up, Down, Down, Left, Right, Left, Right, B, A (for mouse/kb setups, this is arrows, then the letters b and a).

  2. This will bring up a dialog asking if you want to enter cheat mode. Hit Activate Cheats.

  3. Hit F8. This will bring up the debug console.

  4. Typing ukbutt prefs and hitting enter will show all UKButt preferences

  5. To edit a pref, run set prefs_local [pref type] [pref name] [pref value]
    a. For instance, to change strength to 1.0, run set prefs_local float ukbutt.strength 1.0
    b. There is currently a bug where some types will display incorrectly. If you want to change a pref that lists “true” and “false” as its values, use the following command: set prefs_local bool [pref name] [true or false].
    c. i.e. to turn menu haptics off, you’d use set prefs_local bool ukbutt.enableMenuHaptics false

That’s it! If you have any issues with the mod, please comment below.


Mod Prefs show up in console, but won’t connect to Intiface Central

Check to see if you have UMM installed. Look at the directory listing of your BepInEx/Plugins directory.


If there is a UMM directory, that may be an issue. Try removing it unless you need it for other mods. If you already had other mods installed and want those plus UKButt, please reply here so I can help debug.

1 Like

Unable to open debug console in ultrakill despite cheats being enabled? Plus the license file isn’t included in the latest release of the mod?

license file doesn’t matter, but yeah, parts of the mod may be broken because of the game updates lately

…somehow i didn’t think about that at all. well shit lol.