Please contact Swept or LocalHyena on Discord if something in this guide is wrong or outdated. Clarifications There are two ways to mod Abiotic Factor. PAK Loading involves using the Unreal editor to pack your own content files for the game that will load after the original game content files. This is commonly used to make simple asset-swap mods like for example the Half-Life Audio Replacement mod. This method works well, but has a limit to it's functionality. Any asset defined in a pak will literally replace the asset, so if you have multiple pak mods that replace the same thing, you'll run into problems fast. UE4SS is a robust mod injector (among other things) for Unreal games. There is a purpose-built version for Abiotic Factor here. Documentation for UE4SS will not be discussed in this guide, since it already has lots of documentation - but if you want to make complex modifications to Abiotic Factor or add new stuff to the game than this is your tool.