Monster Hunter Frontier Z (MHFrontier or MHF) was an online Japanese massively multiplayer online role-playing game (MMORPG) set in the Monster Hunter universe. In 2019, its last official server closed, giving rise to a community-operated constellation of servers.
As one of these server operators, I began working on a suite of tools for modding, editing, and patching MHFrontier. This guide will walk you through the process of running a custom server and creating client-side modifications.
Running a custom server
To start playing MHF, you’ll need to connect to a server. Luckily, ZeruLight/Erupe is an open-source implementation that makes this process relatively straightforward. I won’t delve into the details here, but you can find more information on GitHub.
Getting a client
With at least one server running, you’ll need to obtain a client. This step is slightly more complex due to licensing restrictions, even though Capcom no longer enforces them. You can find various links and open-source implementations online. I contributed a language pack for the client, making it easier for players to access the game in their preferred language.
I mainly contributed for a language pack for the client, since the original game is in Japanese only.
Client files edition
Once you have the client installed, you may want to edit its data, such as creating a new language pack or patching existing files. However, editing the game data is not straightforward as the game data are encrypted and compressed.
I forked an existing tool to create houmgaor/ReFrontier, which features significant interface changes and speed gains.
3D assets
The Monster Hunter universe boasts a variety of iconic creatures. To access there 3D models for the creatures, I worked on a Blender add-on called houmgaor/MHFrontier Blender Addon, forked from a previous add-on. This fork brings compatibility with Blender versions above 2.7 and documentation to actually use the tool. This add-on allows you to import and work with MHF’s 3D assets in Blender.
Text data translation
MHF contains an overwhelming amount of text data, making a 100% language pack challenging to create. To simplify this process, I created FrontierTextHandler, a simple tool that converts processed binary files (produced by ReFrontier) into CSV format. This allows you to easily edit and translate text data using external tools.
This tools takes a processed binary file, as produced by ReFrontier, and creates a CSV with the data inside. Below is an illustration of the output from the English patch, not the original Japanese translation, but the process is exactly the same.
| location | source | target |
|---|---|---|
| 12173472@mhfdat.bin | −−−−−− | −−−−−− |
| 12173476@mhfdat.bin | Book of Combos 1 | Book of Combos 1 |
| 12173480@mhfdat.bin | Book of Combos 2 | Book of Combos 2 |
| 12173484@mhfdat.bin | Book of Combos 3 | Book of Combos 3 |
| 12173488@mhfdat.bin | Book of Combos 4 | Book of Combos 4 |
| 12173492@mhfdat.bin | Book of Combos 5 | Book of Combos 5 |
| 12173496@mhfdat.bin | Alchemy Guide | Alchemy Guide |
| 12173500@mhfdat.bin | Potion | Potion |
| 12173504@mhfdat.bin | Mega Potion | Mega Potion |
| 12173508@mhfdat.bin | Nutrients | Nutrients |
The three-columns system simplifies the translation with external tools. Once you created new translations on the third column, you can send the data back in the original file (mhfdat.bin here) using FrontierTextHandler. Then, compressing the data with ReFrontier you have a new in-game translation.
Conclusion
With these tools developed, you can play and interact with Monster Hunter Frontier Z in ways previously impossible. As the game is no longer maintained by its original company, this is an excellent opportunity to learn game modding and edition while having fun with the community.