Tl;dr: Modding Digimon World 2 with a Romhack that restores some cut content and fixes some problems.
Digimon World 2 for PS1 was a strange game. It's one of the objectively badly designed RPGs with unethical amounts of grinding, and repetitive gameplay. Yet, it's a game that I'm hugely nostalgic for.
Throughout the years I've played Digimon World 2 countless times, but never beaten it once. The gameplay loop is enjoyable after not experiencing it for years, but it eventually gets boring before I reach the ending. If you want more of my opinion on this game, read my retrospective here.
Just recently, I found out about The Improvement Hack. A patch for Digimon World 2 by Gledson999 The patch fixes some problems in the USA ROM of Digimon World 2, restores some cut content, and adds new Digimon and Dungeons to the game.
This Rom-hack adds the elusive Blackwargreymon: A Digimon that was rumored to be in the game but it turned out to be yet another pre-internet urban myth.
The Blackwargreymon in this hack is not Capturable.
This link has a list of all the changes, but the important difference is that it re-adds content from the Japanese version, that was cut from the USA version due to Localization & Code Limitations.
One example is Kimeramon being activated on floor 99 of Terra Tower. (Finally... It's not accessible in the main game without cheats, or so I've heard.)
Digimon like ModikiBetamon, Sharmamon, and Auroramon were added to the normal dungeon encounters where they should've been. Because of that, the Improvement Hack is slightly harder than the original.
The hack does some fixes to things like portraits and tech names. It restores the Pocketstation Integration, (originally a Japanese exclusive.) The hack also adds an Exit button in-game to return. In the original version, you can't return after starting the game, and can only view the screen when you reset the Playstation/Emulator.
All-in-all, the hack changes the game in small but noticeable ways. Especially for someone like me who played the beginning parts of the game many times, the hack changes the first battle noticeably.
I played this hack on DuckStation Emulator. My favorite Playstation 1 Emulator in recent years. Screenshots are taken from the Linux version but I also use the Android ver. from time to time.
At first, I needed to patch the game. I already had the USA version of Digimon World 2 in my PS1 games folder. I had to download the hack itself and download the xdelta patcher.
While xdelta is straightforward to use on Windows, I was using a Linux machine at the time, and it was harder to install. Until I realized I just had to install it with a terminal with a simple "sudo apt install xdelta3."
Another thing I needed to learn is how to use Xdelta3, and after a full hour of researching, I finally found the right arguments to use:
xdelta3 -d -s [original_file] [delta_file] [new_patched_file]
-d = Decompress, it's used to apply the patch.
-s = Source, it takes the files as arguments to pass to xdelta
For each file, the path must be provided. The order is important
Thanks, Youtube Stranger.)
I needed a bunch of tries to get it right, I got a strange ISO that the Emulator wouldn't recognize a bunch of times, but when I succeeded, I knew it from the size of the new ROM.
Finally, I decided to play with the Emulator's settings for a bit. I changed the internal resolution to x2 and used the xBR filter at first. The result was gorgeous, but it when the screen showed too many effects, (Digimon World 2 does that a lot,) the game slows down.
Eventually, I removed the xBR filter, tried to do some Downsampling which steered the experience closer to an authentic PS1 experience, then finally settled on adding "scanlines" in the post-processing section. The scanlines didn't slow the game down, in fact, in turbo mode, it can go to 5 times the original speed.
This experiment made me realize how much toll filters like xBR and JINC2 have on the machine. Bilinear doesn't use that heavy resources, but I never liked how the bilinear filter looked.
After that, I played Digimon World 2: Improvement Hack for a few hours. (Stayed late at night out of excitement.) I encountered most of the originally missing Rookie Digimon.
All of these Digimon are partnered with ones that were in the original version of the game. For example, Psychemon acts as the third enemy in an encounter that originally only had Gabumon and Gutsomon as enemies. You can imagine the challenge this added to that encounter. If this trend continued, Digimon World 2 will become quite challenging indeed. I heard that there's another mod to up the challenge even more... But that's a story for another time.
I haven't played enough to recommend this Romhack to everyone, but I can at least recommend it to those who are familiar with Digimon World 2 and want to replay it. Though because of its grindy/repetitive nature, I'll never recommend the game without an emulator with a Turbo Mode.
I hope this article was helpful.~
For more of my Digimon World 2 articles, check my retrospective review and my nostalgic experience. If you're interested in retro games, you might enjoy learning about Analogue Pocket or buy a ShonenJump NES Classic with cryptocurrency.