Hello everybody! Some of you may know that at one point I made a few mods for Sonic Adventure DX, which allowed the game to use Dreamcast textures on the PC version. Later on, PkR and some more people would develop the Dreamcast Conversion. If that’s an odd sentence to start off, it’s because I was (and still am) part of X-Hax, a group dedicated to SADX modding. I’m also one of many fans Sonic Adventure still has after it’s release, 21 years ago.

For an quick preface, Sonic Adventure is one of the series most known entries. This is because of the reception it had in the community, the fact it was the hedgehog’s first entry into 3D, and how it is still referenced by many as one of the best 3D Sonic games. On a personal note, I discovered Sonic through Sonic Riders and Sonic Adventure 2 Battle (as I had both on my Gamecube). From there, I started playing around with SADX Demo Version “A” on my PC years ago, before getting to play the whole thing, and then started to look around at the amount of research done for hacking it. I initially tried out the Trainer that allowed you to play as Super Sonic and change things on the fly.

Like many of the Sonic games in the community, Sonic Adventure DX was a quite popular game for modding, This is mostly attributed to the big research and hacking scene for it, similar to the amount of research and ROM-hacking scene for the Genesis games. Between the strong community of X-Hax, and how people were interested in restoring aspects from the original Dreamcast release, there was a growing effort that went on all these years to make it better. With the interest I had in this, I decided to do this article, trying to document as much as I could find (and knew) about all these years of SADX hacking. It seemed like a good time to do so with the original game being released back in 1998, and the PC port of SADX releasing 16 years ago in the year of 2004 (the hacking scene would start at that time, getting popular around 2008-2009).

Writing this article would involve getting to talk with X-Hax mainstays who were around at the beginning, as well as investigating the earliest modding efforts of the scene. From there, I covered the popular character mods (which were characteristic of Sonic fans), investigations of the game’s prototypes, and, of course, the time when the tools and knowledge evolved to the point of bringing in a new era in the game’s existence. This provided mods that would finally give the original game, and the intentions behind the team that made it, proper justice.

But, of course, trying to understand the importance of these milestones, and the reasoning behind these efforts, may be difficult without proper context of Sonic Adventure and all the re-releases it received. It is important to first go through the story of Sonic Adventure itself and what the ports it later received changed from the original.

As a start, Sonic Adventure originally got released for the SEGA Dreamcast in December 23, 1998 in Japan, right before Christmas. It would later be released overseas during September 9, 1999 in North America (which was clearly on purpose, noting that the numbered date goes “9/9/99”), and October 1999 in the European countries. There was also an “International” re-release for Japan.

It was Christmas 1999 when I got my SEGA Dreamcast. I distinctly remember my parents asking me if I wanted it because it was advertised with Sonic and Knuckles CGI renders, and Knuckles was my favorite character.


The original Japanese version would have several unchecked glitches that would later be fixed by Sonic Team USA in the international releases. The Japanese international re-release would have the same fixes and also offer an English dub, the original Japanese dub, rumble support, and camera angle alterations.

The first Japanese trailers for Sonic Adventure were seen through an October 1998 Dreamcast promotion disk (these trailers contained beta footage). Another two were shown on release day.

While nowadays the reception for Sonic Adventure as a whole is somewhat divisive, there are still many fans of it out there (including myself). Back in 1999 it was the very first, proper, 3D Sonic game in the series, as well as his first new console appearance since the Genesis/Mega Drive era (having skipped the Saturn).

It was a very playable game on top of having advanced graphics for it’s time. Sonic Adventure also garnered an extremely positive reception from magazines when it first released.

One day I saw a relative playing a 3D Sonic game (SA1) and I got to play for a bit. I think I managed to play as Knuckles in Speed Highway for a few minutes but that’s all I got to play at the time. […] It looked better than R and I think that was also the first time I ever saw a Dreamcast, so I was wondering what the thing even was.


As an example, here is a review from the release month. It does point out some unfortunate features of the game that are often mentioned today, like Big’s section being less interesting than the rest of the game and Amy’s English voice. But overall it praised the game as you can see:

While it would be more fun to have some really quirky problems to solve in the adventure sections of the game, it is the individual levels that will have you returning to Sonic Adventure time after time. […] Despite many regrettable aspects (Big Cat’s fishing adventures are slightly less exciting than looking at grass, though graphically pleasing) it is the first genuinely must-have game avaliable for Sega’s kick-bum console, with it’s eye-candy-style graphics, loveable characters, funky badly-translated Japanese music and tooth-gnawing challenges, there are few games more likely to have you playing well past Christmas like Sonic Adventure. Just turn down the volume whenever Amy Rose starts peaking, and you’re away!

Jem Roberts, Issue 1 of Dreamcast Magazine (UK), Paragon Publishing, November 1999

It would be the the first attempt of several to bring the blue blur into the three-dimensional playfield, and it would be considered one of the most successful attempts in the franchise despite the shortcomings of a game developed under pressure during the start of the Dreamcast’s lifespan.

The game took advantage of new hardware capabilities like texture filtering, 640×480 screen resolution, specular effects (like shiny windows and cars), true transparency (used for translucent water, effects, and the titular Chaos, a recurring enemy in the hedgehog’s adventure), Day/Night cycles, along with an colorful lightning implementation and overall being able to push much more polygons on sprawling scenes than what was possible before. The action levels were packed with visual details and the large Adventure Fields.

My father and I were at a computer show and a vendor was using the Emerald Coast demo to show off his monitors. The instant I saw it I was stunned. A 3D Sonic game? It was so fluid and smooth, and this time there was so much depth! It felt like my first encounter all over again. I asked the vendor if I could play it, and he said I could. Well, I would up playing it over and over again until he eventually kicked me off the unit. 


Now, while Sonic Adventure would be a successful flagship game for the SEGA Dreamcast, the role that SEGA had as a console manufacturer would come to an end in March 23, 2001. The only direct sequel to it, Sonic Adventure 2, would release a few months after the Dreamcast’s official discontinuation.

With that said, SEGA would become a third-party developer, creating an alliance with Nintendo who was SEGA’s toughest rival during the times of the Sega Genesis and Super Nintendo. Sega developed several games for Nintendo’s console that generation, the Nintendo Gamecube. Billy Hatcher and the Giant Egg, Phantasy Star Online Episode I & II, Skies of Arcadia Legends, Sonic Mega Collection, and several others would be part of SEGA’s lineup for this console; among which you may have noticed some Dreamcast ports.

Oddly enough, it would first receive a port of Sonic Adventure 2 in 2002 with a “Battle” subtitle added to promote the extra additions in the multiplayer mode. But the following year would see the original entry resurface on Nintendo’s newest console, also with an additional subtitle.

Sonic Adventure DX: Director’s Cut would arrive on June 17, 2003 in North America. It included several additions, like a Mission mode, a revamped Chao Garden system (mostly lifted from SA2), and the interesting addition of the “Mini-Game Collection” which contained 12 unlockable Game Gear games starring Sonic. It would also introduce a sizeable number of changes to the game’s visual design such as the menus and HUD interface, or, more important things, like the level textures, level models, and even the player character models. The lighting in the game would also be rather different because the original lightning engine was missing. It would also try using a 60fps framerate, instead of being locked 30fps like on the Dreamcast, with mixed results.

While the Gamecube port would be serviceable, and keep the gameplay intact, reception would be mixed compared to the original. Many of the game’s physics quirks were left untouched (and thus, would be seen by some as quite buggy) and the visual changes were unappealing to a good portion of the playerbase. On the other hand, it would have more consistent results than ports that came later.

The Windows version of Sonic Adventure DX appeared in 2004. While this version would have the same content as the Gamecube port (minus the Game Gear games) there were MANY weird things about the PC port. To start off with, you couldn’t change the keyboard mappings and the windowed mode was a fixed size. On top of that, there would be many additional issues with ported assets, worse textures, and poorer sound quality. Here is a quote from PkR’s Dreamcastify site, which was created to extensively document all the downgrades in SADX ports:


The Gamecube version is inferior to the original game in many ways, but the 2004 PC port has even more issues, with more bugs and even worse lighting, texture and sound quality. The nextgen console ports and the Steam version have even more issues than the original 2004 PC port that they are based on.

PkR, Dreamcastify

The newer ports for the PS3 and X360 would be based on the 2004 PC port, keeping the same problems and creating new ones on top of them. Reception was again mixed this time due to the aged graphics and further broken gameplay. This version would again be ported in 2011’s release of the SEGA Dreamcast Collection for Windows. The collection kept the same issues as the previous port despite being marketed as “the Dreamcast original”. Quoting again from Dreamcastify:

[…] SADX is a massive letdown that not only fails to convey the atmosphere of the original game, but is also riddled with technical issues and design problems. The broken ports are still being advertised and sold on Steam, the Playstation Network and the Xbox Marketplace as the supposed “definitive” version of the game. These ports are such an incredible mess that people who play them first get a negative impression of Sonic Adventure, thinking it has always been a terrible game.

PkR, Final words (November 6, 2017), Dreamcastify

With that said, the existence of the 2004 PC port has allowed for MANY good With all the above said, the existence of the 2004 PC port has allowed for MANY improvements to be made to the game. This is thanks to both a huge effort from the community (Sonic Retro, and to a larger effect, x-hax) and the fact that PC games are often moddable after enough documentation has been done. Things like restoring the original Dreamcast levels, models, sounds and many other things have become possible. On top of this, tools have become more flexible to use nowadays.

That’s not to say things like custom character models (which were the most common mods in the early SADX modding scene) and custom stages (which began to appear more often as knowledge improved) weren’t around in earlier days. Overall there is a long history of cracking open Sonic Adventure DX in Windows (as well as most of the Dreamcast and Gamecube versions), as there is with many other games.

A mod for SADX with Egg Fleet level from Sonic Heroes. Note the usage of Lantern Engine (the lightning on Sonic) and high-resolution with ModLoader, while keeping Sonic’s original DX model (except with some textures altered).

Now, with all of this information in mind, we are going to investigate the many milestones accomplished by the SADX modding community and their research of the 2004 PC port of Sonic Adventure DX. We will also take a look at the tools they’ve developed and how mods were created for the game. Without more to say, this is The History of Sonic Adventure DX Modding.

The original concept was to have all the sections in a single article; but as a way to allow some gradual ease in reading the whole thing, these sections that cover the entire topic will be spread out in separate posts. You can find the next one and all the others in the index below.