There are two games that bring back a large amount of nostalgia for me: Diablo 2: Lord of Destruction, and another lesser-known MMORPG called Ragnarok Online. In the end, both of these games provided a bit of an isometric (or on RO’s case, 2.5D) perspective of the world, provided combat, itemization, and many years of fun. One thing I’ve always had as a dream was to eventually make a clone of the merger of both: Ragnarok Online graphics, with Diablo-like equipment and itemization.

To achieve this goal, I’m going to slowly tackle the concepts that make up Ragnarok Online, in no particular order… starting with the one format that can help me with unlocking all of the resources I could ever need: The GRF format, or “Gravity File” format. This was effectively a ZIP file (which may or may not have had compression, I have no idea yet) that provided a way to store and retrieve the many graphical, musical, or data resources that made up the game.

I’m aware that there are existing tools out there to be able to view/modify GRF files, but part of the fun of computers for me is learning how it all works, all the way down. So I’m going to lightly start there, and ensure that when it comes to “my implementation” that will one day come, that we eliminate as many of these proprietary formats/standards, so that a large company will have less grip on any of the systems that make up the game.

In the past, I’ve tried looking up some of these formats..

• GRF for the actual catalogue of files
• GAT file for “ground altitude” data that listed out the tiles
• … and there’s gotta be some interesting model/texture/animation formats we’ll find

In the end, my hope is to take some steps of a Github repo for storing progress on this front.