Welcome to chaoskaiser72's ONScripter Corner!

... And because it may well be that small limited visual novels -- written by small limited hands and running on small limited systems -- are the last and best virtual reality that we have ...

ONScripter is a Free & Open Source implementation of the NScripter novel game engine, based on SDL and licensed under the GNU General Public License v2. It allows many popular novel games to run on a plethora of platforms such as Linux, BSD, Mac, OS/2, and a number of game consoles; most importantly, it can be easily modified by the community.



...And so, we have ONScripter-EN: a fork designed to handle English scripts containing 1-byte characters in a better way. Although the original ONScripter is still maintained, it lacks fully functional English support, DirectSound support on Windows, PNG alpha mask detection, window scaling, and many implementations of effect DLLs -- all of which were added to ONScripter-EN long ago. ONScripter-EN was originally forked by Insani, passed on to Haeleth, and ended in the hands of Uncle Mion of Sonozaki Futago-tachi. It was abandoned in 2011 and Mion's site went offline in late 2018, resulting in many resources becoming hard to find. As such, I have provided the Download Mirrors section for the last stable builds and source code, and my own revision of the (O)NScripter Command Reference for any and all development needs.

New Development

A good acquaintance of mine, Galladite27, contacted me in 2022 intending to take up my ONScripter-EN development bounty. Kept quiet for the longest time, he now has made progress beyond what I had imagined, and the new ONScripter-EN is being developed with help from GP32 of Insani, with some features backported from his own ONScripter-insani. The new repository is located here on Github.

Runtime Basics

Note: It is imperative that you update to the latest version of ONScripter-EN before attempting to run a game, especially on a recent operating system. See Updating ONScripter-EN Games.

ONScripter-EN will not start without a default.ttf font file in the game folder. Since the engine displays text only with fixed width, and some games like Umineko and Tsukihime use Japanese or custom glyphs in their English translations, Sazanami Gothic is the standard-use font for most releases. If you are scripting your own novel and must use a proportional font, see PONScripter or ONSlaught.

The original NScripter had a menu bar which let you adjust all the settings; it was never implemented in ONScripter for compatibility's sake, so you use keybinds to access the same functions. For a rundown of these, see the Readme.

Please also see List of Known ons.cfg Options.

High-Resolution Scaling

In addition to pressing F for fullscreen, on reasonably recent versions you can scale your ONScripter-EN games to virtually any size, including but not limited to 1080p. Text scales beautifully, and it makes reading in windowed mode much more comfortable. In order to scale a window, make a text file named ons.cfg in your game folder. Then, simply add the line ...



window-width=[desired width]

The scale option automatically adjusts to the maximum vertical size of your screen, while window-width allows you to set any value you like. Do note that scaling up the window will lessen the impact of text shadows, decrease framerates where heavy effects are in use, and may introduce some image-related jank. If it does not work, see the Updating ONScripter-EN Games section.
Note: This config option will not work by default for Kagetsu Tohya due to a bug in its script: I have made a patch for it, including the latest ONS-EN, which may be found here. See readme2.txt for instructions and further details.

List of Known ons.cfg Options
window-width=[value in pixels]
root=[alternate path to game resources]
save=[alternate path to store save files]
automode-time=[value in milliseconds]
waveout-audio (for Windows to favor waveout over DirectSound)
audiodriver [dev]
audiobuffer [size in kbytes; 1,2,4,8,16 allowed]

All of the above can also be passed as command line options at runtime, for example:

onscripter-en --scale

To clarify some of the commonly-used options, english or japanese is used in cases where one might need to force a language mode, detect-png-nscmask detects whether or not PNG files use NScripter alpha masks (necessary for Witch Hunt's Umineko), strict is used to treat script warnings more like errors, and debug will cause the engine's output and error files to open upon the game's exit (or crash). An ons.cfg file is supported only as of build 2009-09-30. Please see Updating ONScripter-EN Games.

Updating ONScripter-EN Games

It is necessary to update all of your ONScripter games to the latest version of ONScripter-EN. It fixes crashes on recent Windows versions, adds important features which were not previously present, makes it possible to use ons.cfg options, and allows you to keep all of your save files in one convenient folder. Before dropping the latest executable into your game folder, make a text file named game.id, containing ONLY the name of the game: this determines the name of the folder in which your save files shall be stored (If you neglect to do this, saves are stored in randomly-named folders). Then, download the last ONScripter-EN build for Windows (with SDL), Linux (x64), or Mac OS X, and unpack to your game folder.

RaspberryLime has made a Windows batch script, AONS-ENSU, which will automatically update ONScripter-EN games, add a game.id file, and set an ons.cfg file to keep game saves in each game's folder rather than in C:\ProgramData\. It requires minimal input from the user, but bear in mind that you will need to point any existing shortcuts to the new ONScripter-EN executable.

Note: When updating Umineko no Naku Koro ni, you must add detect-png-nscmask to ons.cfg in order for the English image assets to display correctly.

With these recent versions of ONScripter-EN, by default each game's save files are kept in their own folder within the hidden directory C:\ProgramData\ (Windows 7+) or ~/ (Linux/BSD). This is so that games can be kept in any folder -- even ones that are not writable.

Due to radical changes in Mac OSX, the existing builds of ONScripter-EN for Mac have many bugs by now, and some have reported that the Linux builds will not run on Wayland. If you have issues on either platform, it may be more practical to run the latest Windows version in Wine instead.


The legendary translation group Insani just came out of retirement after fourteen years, and alongside two new (old) translations, they are providing a new ONScripter fork: ONScripter-insani. Originally, ONScripter-insani was the first English-compatible ONScripter branch; today it is a new fork off the main branch, with English compatibility features added back in, in order to be as up-to-date as is possible.

ONScripter-insani retains the full source code of the main branch, along with its legacy SDL1 dependence: by omitting the INSANI flag, Ogapee's stock ONScripter will be built. ONScripter-insani itself is built only for 64-bit Windows and Mac, relies on SDL2, and according to insani's NScripter About/FAQ, is not intended to replace ONScripter-EN as it is purposely limited in how far it may deviate from the main branch.


PONScripter stands for Proportional ONScripter. It essentially is a fork of ONScripter that supports Unicode, so proportional fonts and many more languages are supported, and it is generally more flexible and modern. However, it was abandoned early into its development, so even on the latest forks it is highly unstable and unfeatureful. It uses a bit more resources, has many more bugs and behavior issues, and it is not fully backwards-compatible with NScripter nor ONScripter. Support for Japanese filenames is dropped, and new routines and syntax are required; meaning that porting an NScripter game to it is a significantly involved effort. PONScripter does have a legacy mode which runs NScripter and ONScripter-EN games as they were written, but most of its issues are still present. More importantly, PONScripter does not support some custom effects which NScripter and ONScripter-EN do, which results in the MangaGamer version of Umineko and all versions of Umineko Saku lacking the animated rain effects completely -- many NScripter titles made use of external DLLs which were later merged into ONScripter-EN by means of emulation, so this presents a huge disadvantage for PONScripter. The main branch of ONScripter now supports both proportional fonts and Unicode, so PONScripter almost can be considered obsolete, save for that PONScripter still has the best support for Western languages.

PONScripter is used nowadays in Steam localisations of NScripter games, so the code was forked by SekaiProject in order to port it to SDL2 and keep it maintained. You can find it here on Github. Witch Hunt made their own fork of the SekaiProject fork, and are using it for their translation of Ciconia no Naku Koro ni. The many versions of PONS and the changes across them can cause significant problems when trying to run games on the latest version.

Configuration files come in the form of a pns.cfg file, although window-width and scale options are not supported. Documentation is rather sparse, but the latest manpages are hosted here.

Although PONScripter is highly favored for commercial translations, its instability can present problems. If you are a translator and your language features special characters such as diacritics, you may find it best to use ONScripter-EN and edit a font so as to assign special characters to unused supported characters. Many translations have done things to this effect, such as Mirror Moon's English translation of Tsukihime assigning the ellipsis character to |. This method saves you an incredible amount of engine-related headache, although at the cost of producing a script which is bit more complicated to edit.


ONScripter-RU is yet another fork, but it is probably not for you. If you wish to make a Russian translation of something, consider PONScripter or ONSlaught. ONScripter-RU's only major usage is in the Umineko PS3 project, and it does not work with much of anything else. As stated on its Github page, ONScripter-RU makes use of its own hacks, so don't expect cross-compatibility between it and the other forks.


Befitting its unique name, ONSlaught was not a fork at all, but rather an attempt to program an NScript interpreter from the ground up. Its developer was annoyed by ONScripter's (former) lack of Unicode support, and the fact that support for languages other than Japanese was splintered across an array of forks. ONSlaught supports Unicode, can fake bold/italics, and is able to run very basic games such as Tsukihime and OMGWTFOTL, but some core features such as text sprites are not working. It is much more strict and consistent in its handling of syntax and errors, so in order to use it you likely will have to make some edits to your game script. It is known to have been used in Tsukihime's Spanish translation and its Russian translation. ONSlaught was abandoned in 2011, although the developer may be open to fixing its most outstanding problems at some point.

ONScripter Plus

ONScripter Plus is an Android app that runs ONScripter and ONScripter-EN games pretty much how they should be run. Of all the incarnations of ONScripter on Android, this is the one to pick. It bears a few bugs and may have some save file issues, but it is a great way to read your novels while away from the computer. Although it requires a small workaround, this is the only interpreter on Android which supports proportional characters and UTF-7 and UTF-8 scripts, making it a viable alternative to Unicode-compatible interpreters which are not available on Android, such as PONScripter and ONSlaught. You might consider buying the ad-free version for to support the developer.

ONScripter Windows Builds

Since the main branch of ONScripter includes build instructions for Windows yet no actual builds, I took it upon myself to make my own 64-bit Windows builds for your convenience. I had meant to update these with each new release, but it seems Ogapee removed the ability to enable or force 1BYTE_CHAR in the source, so I'll just leave these here for now. Do note that ONScripter lacks several important features that were included in -EN many years prior, so it probably will not suit your English script needs, unless the game you are trying to run was made very recently.
I really wanted to make 32-bit builds as x64 is extravagant for this use-case, but Ogapee has provided no way to do so on Windows.

ONScripter - Version: onscripter-20191022


ONScripter-EN Historical Mirrors

Here are the same downloads of ONScripter-EN and the ONScripter tools that were on the Releases page of Uncle Mion's site, now mirrored on the Wayback Machine. Do note that these builds are provided for historical purposes, and ONScripter-EN now is in active development again here.

Version: onscripter-en-20110628

Source Packages:

Version: onscripter-en-20110930

Source Packages:

ONScripter Tools - Current Release (2010-09-15)

PONScripter Download Mirrors

PONScripter is not an ONScripter replacement: it is abandoned software which lacks much compatibility. Use at your own risk.

Version: ponscripter-20100502

Source Packages

General Resources

I have updated the *NScripter command reference, fixing some old errors and adding several new commands along with more engine information. View it here.

To access what remains of the official ONScripter-EN/PONScripter support page, visit Uncle Mion's ONScripter Corner on the Wayback Machine.

The NScripter-related page of a previous maintainer of ONScripter-EN, Insani, is still up. Haeleth's site sadly is down as of spring 2020. The builds and source code on these pages are very outdated, but you may still find some use in them -- specifically, Insani hosts the Japanese NScripter SDK and extraction tools, which are no longer necessary for us but still have their uses. Also check out insani.org's main page for many free English-translated NScripter games -- see Updating ONScripter-EN Games before running any games obtained from here.

If you can read Japanese, the home of the original untranslated command reference, Senzogawa's NScripter Scripting Factory still is up.


Some brief mentions of popular English-translated games that run on ONScripter-EN -- full list here.

A likewise non-exhaustive list of games that use PONScripter:

You will find that many translators' sites refer to online store/download links which no longer exist. Many of these games are long out of print, so even if you bought second-hand copies, the developers would get none of the proceeds. As a result, you may have to find downloads on Rutracker or similar sites. If you go this route, please support the original developers in whatever way you can, if applicable and/or possible.