Utilla for Gorilla Tag – Modded Room Library (1.7.2, sirkingbinx)

Utilla isn’t a mod you notice in-game. It’s a small PC library, written by legoandmars, that other BepInEx mods lean on to answer one question: “am I in a modded room right now?” The GitHub description calls it “a PC library for Gorilla Tag that handles various room-related things (and more?)”, which is honest about how unglamorous it is. If a mod’s install notes say it needs Utilla, this is the file.

What Utilla actually does

• Modded-lobby detection. Mods built on Utilla only switch on when you join a modded gamemode. Since Utilla 1.5.0 that’s a requirement for mods using it, not just a private room. This is the main reason the PC modding scene treats Utilla-based mods as safer.
• Custom gamemodes. Mods can register their own gamemode, and it appears next to the normal modes on the in-game computer. Fully custom game managers can’t use matchmaking, but still work through room codes.
• Developer hooks. Plugins mark themselves with [ModdedGamemode] and get join/leave callbacks ([ModdedGamemodeJoin], [ModdedGamemodeLeave]).

Details

• Author: legoandmars (GitHub)
• Source: github.com/legoandmars/Utilla (MIT license)
• Original repo’s last release: v1.6.14, published June 26, 2024
• Maintained fork: github.com/sirkingbinx/Utilla, latest 1.7.2 (October 5, 2026). Use this one: mods such as Walk Simulator note that Utilla 1.6.27 and older no longer load on the current game
• Platform: PC (Steam / PC VR) only. It’s a BepInEx plugin, so it does nothing on a standalone Quest.

Installing Utilla

The README gives two routes.

With Monke Mod Manager: tick Utilla in the mod list and install. The manager handles BepInEx too.

Manually:

1. If the game isn’t modded yet, install BepInEx first: extract the x64 BepInEx zip into your Gorilla Tag folder and run the game once so it builds its folders.
2. Download the latest Utilla release.
3. Extract it straight into the Gorilla Tag folder, not into a subfolder. That last part is where most installs go wrong.

Things to know

• The last release is from mid-2024 and the repo hasn’t been pushed since July 2024. Gorilla Tag updates have broken older PC mods before, so if mods stop loading after a game patch, check the repo issues before reinstalling everything.
• If a Utilla-based mod “does nothing”, you’re probably in a normal public lobby. That’s by design. Join a modded gamemode from the computer.
• Don’t stack two copies of Utilla in BepInEx/plugins. Remove the old folder before extracting a new version.

Utilla FAQ