Ramblings

You are lucky! For the longest time, extracting assets from Unreal games was the biggest pain in the ass you could imagine. In fact, I collected an ungodly list of tools for entering Unreal games, but you will only need one: FModel. I created an entry in my list of tools, but you can just google for it or take this direct link to their Github page.

Fmodel is quite amazing - for beginners, It does the job of dealing with .pak and .utoc archives. Back in the days, you had to do this with a funny script that you downloaded from a funny website, which then revealed .uasset files which you had to load into a different program that then let you extract files from there. Back then you needed QuickBMS, and then you needed UModel, and then you needed a way to figure out WWise. Fmodel does all of this for you!

Additionally, there are some good odds that you will need jmap. See their Github page. You will probably be interested in the jmap_dumper-x86_64-pc-windows-msvc.zip file.

In many cases, it can be useful to make a copy of the game folders. This way you can work on the game files without touching the actual installation of the game, ie. you don't break anything. This is not strictly necessary but I like to do it to have a distinct “working directory” instead of working with the live game files.

Your main weapon of choice will be FModel. The important step to working with Fmodel is configuring it correctly. On the top menu, open Settings.
Ignore the exact settings shown in the screenshot. This is to be used for orientation so that you know where to look at. For now, you should focus only on the strictly necessary settings. The strictly necessary settings here are marked with a star:

• Output Directory is the folder to which Fmodel will extract when you extract files. This can be anything, select something convenient.
• Archive Directory is the folder containing the game files. This can be the files from the actual game folder, or it can be a copy of the game folder you placed elsewhere. Importantly, the selected folder must contain the .pak and .utoc files.
• UE Version is the version of Unreal Engine that was used during development of the game. See below for help on determining this.
• Texture Platform is a setting that determines how the game's textures will be read. Unreal Engine saves them differently based on platform, if you are extracting from the files of a Desktop game then you will want to select Desktop/Mobile.

During settings or after, FModel will potentially ask you to restart. Let it do that and you should now be looking at something like this: Again, the exact details here don't matter. What matters is that you see a list of files on the left and a blank screen on the right.

On the top left you will see an option called Loading Mode with a dropdown menu. Open the dropdown and select All. Then hit the Load button underneath.
You should now be looking at something like this:

Congratulations, you are in! (You will have to do this every time you boot up FModel. It does not automatically load in the archives when opened.)

To use FModel, you will now be primarily interested on the right side of your screen that acts as an explorer for the game's files. Use it to navigate through the folder structure, double click to open files and right click to see options for extracting the selected files. After opening a file it will often show a preview - use the left button on the bottom right to get back to the file/folder view.

This is a good start and will often already get you pretty far into the game's assets. Thanks to FModel, you don't even have to worry about WWise or other audio handlers, as FModel lets you play .wem and .bank files right inside the application and allows you to export them to .wav so that you don't even have to ever touch any WWise related stuff.

However, in many cases you will be wanting to look into .uasset files, in which case the program will throw an error in the console below. It will mention “Unversioned Properties” or “Missing Mappings”. These errors are related to how Unreal Indexes its files and is a bit involved to explain. In short, FModel needs a file that maps assets stored in files to.. something? I'm not 100% sure myself, but the importantly what you need now is a .usmap file. To do that you will need to use jmap.

After downloading jmap you should have a file called jmap_dumper.exe. This is a command line program that lets you generate a .usmap file for your game. To do that, you will need to open command prompt and navigate to the folder that jmap_dumper.exe is in.

jmap only works when the game is running, as it pulls its data from the active game process. Therefore you will also need to start the game you're trying to extract from.

Now, look at the following command:
jmap_dumper.exe –pid <pid> output.usmap

Using this command in the command prompt will generate an output.usmap file in the jmap folder. However, you need to specify the Process ID (“pid”) so that jmap knows which process to target. Note that a PID changes every time you run the game, so you have to find the PID yourself. If you need extra help for that, I have added extra information on PIDs below.
A full command could look like this: jmap_dumper.exe –pid 11528 output.usmap. Enter it into the command prompt and hit enter. After jmap completes it work you will see an output.usmap file in jmap's folder.

This mappings file can now be used in FModel. Open the Settings in FModel and toggle the switch “Local Mappings File (Drag & Drop” to on. You can drag and drop your output.usmap file directly into the settings window, or you use the Mapping File Path option below the toggle to specify the directory. Click OK and FModel will probably want to restart. Let it do that, and now when you load in the game files (ie. Step 2), it will do that using the mappings file you provided. From here you can now freely explore the game's archive and extract at your leisure. Feel free to click at every type of file and see what it does. To extract, right click and select what you need (for Audio, for example, you would want “Save Audio”).