MGS2 - Diazepam Restoration(JP)

[worthy dust]

I am a complete beginner to modding, but after being inspired by Afevis's work, I decided to try and restore features from the Japanese version of the game.

As you may already know, only in the Japanese version of SoL, Diazepam appeared following MGS1, rather than Pentazemin. In other versions, it was changed to Pentazemin, consistent with the other language versions.

Accordingly, I want to create a mod that restores the item name, item description, item model, item display name when picked up, and the corresponding radio dialogue. (As mentioned above, since the radio audio to be restored does not exist in non-Japanese versions anyway iirc, I believe this will be a Japanese-version-exclusive mod for the sake of consistency.)

The item models remain in the MC version: dzp_label.cmdl is the label model for Diazepam, and dzp2_label.cmdl is the label model for Pentazemin.
I know I could potentially handle this via model swapping or texture swapping, but since this is intended to be a restoration, I would prefer to handle it by changing the model being loaded if possible.

Also, I have already extracted the corresponding radio audio files in .wav format from the PS2 version.

Where should I begin? Also, if there is a suggestion to integrate this with other mods, I would be more than happy to accept.
I am unfamiliar with so many things, so I would greatly appreciate your guidance.

[worthy dust]

I have only succeeded in changing the radio audio by repacking the .sdt files. (Although the beginning of Pliskin's audio doesn't seem to be playing correctly.)
However, this causes synchronization issues with the animations and subtitles, and I need to fix this, but I have no idea how to proceed.
Also, since Giza's gcx editor is not working, I don't know how to change the radio subtitles either.

Could someone please help me with this?

[worthy dust]

I have noticed one thing: in HDC/MC, it seems that BP did not create new lip-sync animations for the re-recorded audio and instead used the original animations, which causes a sync discrepancy between the audio and the animation. (This is particularly noticeable in the Pliskin radio call below.)

Ironically, thanks to this laziness, it looks like I will be able to complete this mod with almost no editing of the animation files.

However, the phenomenon where the animation becomes about 0.8 times slower when repacking .sdt remains unexplained. I have no idea what to tweak to fix it.

[worthy dust]

I am still helpless against the animation desync, which remains as terrible as ever, but I have managed to adjust the subtitle timing by tweaking the stream data (gcx script?) inside the .sdt file that controls subtitle timing. (The desync was particularly noticeable with the Pliskin's codec call, where there was a gap of over a second between the BP subtitle timing and the PS2 version audio, but that has been fixed in the video below.)

[worthy dust]

The decrease in animation speed appears to be a tool issue caused by repacking with sdttools.

[worthy dust]

Yeah, the work related to .sdt files is probably finished. The timing issues for both the animations and subtitles have been perfectly fixed, so all that is left is to replace the string "Pentazemin" with "Diazepam" and change the label model for the item box being displayed.

It seems likely that these will require using a memory patch, similar to the ones used in MGSHDFix.

[worthy dust]

I succeeded in changing in-game strings by manually rewriting memory in real time. Through this, I have understood the general outline of how to change in-game strings; however, I still have no idea how to change the pop-up when obtaining items, the item names in the UI (not the one in the description), and the label models to be displayed. But once I figure out these methods, I think I'm almost there.

[unique rover]

#modding-general message wait you figure out how to rewrite string in memory? There's a Chinese translation mod that has control description stuck in old ps2 ones problem and the creator don't know how to fix it still.

That's only problem the mod has, I want to help fix it but don't know how to edit it other than gcx.

[worthy dust]

I’m still a bit unclear on that point myself, and I was just about to ask about it.
The screenshots above are all done manually. It simply means that, whilst the game was running, I searched for the string I wanted to change on the memory and manually edited the values at their address to alter it.
That said, I’m still quite new to modding and computing, so I’m a bit worried I might have said something a bit odd lol

[unique rover]

#modding-general message The reply above explain that gcx files are just referring points, so that might explain why some of the weapons and equipments description are just in old PS2 outdated one, simply edit them seem didn't work. So edit string in memory probably the best

[worthy dust]

Ah, so that's how it is as I thought. I think I’ll proceed along those lines, asking various questions as I go.

[worthy dust]

During a memory scan, I accidentally discovered further re-recorded (or edited maybe?) codec call regarding to pentazemin and diazepam, and the audio is now restored.

[worthy dust]

@flat bay , apologies for mentioning you. I wasn’t sure who to ask, but I decided to ask you as you seem to have the most comprehensive knowledge.
I have two questions.

1: Changing the pop-up when picking up an item

I believe the item name pops up when an item is picked up, and I’d like to change this name. I suspect this is rendered using a texture rather than text, so what would be the best way to go about this?

2: Changing the label model displayed

Regarding the label displayed on the item box, I have confirmed that the model for Diazepam (dzp_label.cmdl) still remains in MC. As this model is also listed in bp_assets.txt, I suspect it is being loaded but not displayed. How can I make the Diazepam model appear instead of the one for Pentazemin (dzp2_label.cmdl)?

I apologise for the trouble, but I would be grateful if you could advise me on this matter.

[flat bay]

All good, I forgot I was gonna post here a few days ago

Iirc the English version of either trial or original SoL does have english diazepam lines in its sound bank

1. yes, all those item pickup texts are strings in memory. Will write something up for you when I'm free later tonight

2. iirc they were ifdef compilation flags in the GCX files - having them load the separate model would be quite a bit of effort / require modifying all the GCX, which would definitely be a bit overkill when the only real difference is the single word texture on the label.

[worthy dust]

Thank you for your reply.

Oh, English diazepam lines exist? If you happen to have the relevant audio files, I would be very grateful if you could share them with me. (the files I replaced are vc000501.sdt(unused, but just in case), vc000601.sdt, vc018501.sdt, vc212771.sdt, and vc264471.sdt)

Also, I forgot to ask earlier, but are the item names within the UI likely just strings in memory as well?

Regarding the label model, in short, would a simpler approach be preferable—such as editing dzp2_tx_alp.bmp.ctxr to replace it with ‘DIAZEPAM’, or editing dzp2_label.cmdl to reference the ‘DIAZEPAM’ in ibox_tx_all_alp.bmp.ctxr?

[worthy dust]

I edited gcx in .sdt files located in jp/codec/_bp/.
I know it's "the wrong way", but, yeah, it works quite well.

[unique rover]

after you finish your project, may I ask you how to edit weapons/equipment description strings in memory, so I can try to fix that PS2 control text problem in a mod

although I don't have a JP save with all weapons/equipment to check before and after differences

[worthy dust]

Sure, if there's anything I can do! Although, since I am completely new to messing with memory, I don't think I have enough knowledge to teach you...

[worthy dust]

I didn't think it would work.

i edited .gcx

[worthy dust]

yeeeeeeeees it works

[unique rover]

ah someone discovered this too lol

[flat bay]

yea that's why i was saying you just need to rename it in memory

[flat bay]

Sorry I don't scroll down channels all that much, hopefully it doesn't come off like I was ignoring this!

I'll go through the audio bank over the week, there's sooo many clips haha

Also, for replacing the box, .gcx editing is definitely going after a fly with a bazooka / will conflict with other gcx mods (if you do expand to US support) like https://www.nexusmods.com/metalgearsolid2mc/mods/110

I would definitely recommend switching to the far more surgical approach of just editing the ctxr texture as you asked about before, as the only difference between the two models is that label. that way you can toss it in textures\flatlist\ovr_stm\ovr_jp\_win and never have to worry about conflicting with any other .gcx mods

[worthy dust]

I'm still quite unfamiliar with memory and hadn't paid any attention to read-only areas, so I overlooked that part. I realized this a few hours before receiving this message and was able to confirm that these strings were in memory.

Thank you for sharing the information.

[worthy dust]

No problem, or rather I'm actually grateful for your valuable time.
I apologize for the trouble regarding the English audio for diazepam. Thank you.

Actually, I've already finished editing all the .gcx files for the main story. Since the goal is restoration, I took an approach based on the assumption of "what if the ifdef flag didn't exist and the .gcx was compiled to use dzp_label," rather than the surgical approach.

But, yeah, I think conflicts with other mods should be considered as you said, so I'll switch to it.

[worthy dust]

I touched C++ for the first time to make this change.

[worthy dust]

I’ve been thinking something’s been off for ages whilst messing with memory—I couldn’t believe it could actually be the case—but the character ‘タ’ in the string ‘ペンタゼミン’ within the game wasn’t the katakana ‘タ’ (U+30BF) but the kanji ‘夕’ (U+5915).
I haven’t checked all of the .gcx files, but since even the strings within those were like that, it’s possible it’s been that way for quite some time (could it possibly date back to Substance, which was the first to use the name "Pentazemin" in the Japanese version?).

It may go without saying, but the term "ペンタゼミン" is a proper noun that is unlikely to originate from Japanese, so it should be written in katakana. There is no reason to use the kanji character "夕" (evening).

[worthy dust]

It works for now, so I’ve gone ahead and released it.
As I’ve been changing the item descriptions by editing the .gcx file, I intend to update the code so that this is handled by rewriting the memory instead.
https://www.nexusmods.com/metalgearsolid2mc/mods/132

[unique rover]

https://fxtwitter.com/HEITAIs/status/2060005937617015193

兵隊 (@HEITAIs)

PinkElephantGさん(@pink_elephant_g)がMGS2マスターコレクションのPC版で"ペンタゼミン"を"ジアゼパム"に戻すMODを公開されました
︀︀
︀︀元々2001年の日本語版では"ジアゼパム"だったのですが、海外ではペンタゼミンに変更され、2002年のサブスタンスや2011年のHD版ではペンタゼミンに統一されたんですよね

🐘 (@pink_elephant_g) を引用
︀
MGS2 Master Collection版で、「ジアゼパム」という表記を復元するMODをリリースしました。名前だけじゃなく、再録された無線音声もオリジナル版に戻します。(現状は日本語版のみ対応)
︀︀www.nexusmods.com/metalgearsolid2mc/mods/132

**🔁 7 ❤️ 11 👁️ 741 **

FxTwitter · May 28, 2026, 2:31 PM

congrats complete the restore project

[worthy dust]

Thank you. I still need to work on supporting non-Japanese versions and modifying the description text by rewriting memory to avoid conflicts with other mods, so I'll keep at it a little longer.

If the memory rewriting for the description text goes well, I think I can move forward with helping with the translation mod you mentioned earlier.

[unique rover]

thanks a lot

https://mos9527.com/mgs-corpus/MGS2/JP.html I found it funny that somehow the screenplay book from Master Collection that someone organized into plain texts, ジアゼパム and ペンタゼミン both appear, don't know if it's an error or not

[flat bay]

In case you do wanna check/submit translation fixes for stuff like that, I do have all the GCX & codec calls dumped in the MGS2 & MGS3 community bugfix repos. I did intend for the bugfix comp mods to also have translation corrections (since I know I've heard the Italian translation is off quite a bit too, and English also had a hundred or so typos here and there iirc)
https://github.com/ShizCalev/MGS2-Community-Bugfix-Compilation/blob/main/GCX Fixes/jp/_bp/scenerio_stage_a61a.csv
https://github.com/ShizCalev/MGS3-Community-Bugfix-Compilation/blob/main/GCX Fixes/GCX CSVs/jp/_bp/scenerio_stage_r_sna01.csv

That said, I do also plan on making a system at some point with MGSHDFix where you can place a .txt file beside a .sdt/.GCX with the same name and have MGSHDFix automatically detect & override the strings with that txt's contents to make translation mods even easier. (That way it eliminates the whole mod conflict issue & folks also won't have to share massive sdt files just to change text)