This Legion TD2 mod was originally made for Pennywise, to only allow the mastermind legion Yolo (aka the only good option)
But it was extended to make the option configurable directly in game with a new options tab.

Additionally, this mod will serve as demo/tutorial for the LTD2 modding framework once it is available.
It is therefore copiously commented to help anyone wanting to understand its inner workings.

• Close the game
• If not already done, follow this guide to install BepInEx
• Download the latest release, and drop NarrowMasterMinded.dll inside your Legion TD 2/BepInEx/plugins/ folder
• You are done, you can start the game and enjoy!

This mod is made using BepInEx, which is required to build.
Using JetBrain's Rider, you can use this as quick 'build and deploy' script:

dotnet build;
cp .\bin\Debug\netstandard2.0\NarrowMasterMinded.dll 'C:\SteamLibrary\steamapps\common\Legion TD 2\BepInEx\plugins\';