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CompendiumInsane KSM and os/us scale

Insane KSM and OS/US scale

Table of Contents

What is Insane KSM?

⚠️
Insane KSM and os/us scale is meant for more advance players. At minimum you should be at least 18 VF, but recommended to be closer to 19 VF

発狂KSM or Insane KSM is a term derived from Insane BMS in BMS. Essentially, these are community-created charts made to be ridiculously hard with no restrictions. These charts go past the vanilia 1-20 scale. Most charts start at about 18 difficulty with a lot being about or above 20.

Insane KSM is known for its often unfair and challenging patterns. This is mainly because Insane KSM charts have no restrictions on what they are allowed to do. Normally, certain “illegal” patterns are avoided in vanilia. This is because they are either really hard, unfair, or generally not acceptable. In Insane KSM, these rules don’t apply as anything goes. Some charts are even designed with the intention of keyboard play.

Illegal Patterns
Example of some illegal or unfair patterns.

For more examples of illegal patterns, see Illegal Patterns

Just because a pattern is illegal, doesn’t mean it’s not possible it hit. Here is a video of 김가루  playing a chart that has only illegal patterns and getting a perfect.

Examples of charts from Insane KSM:

Insane KSM charts come out in packs or packages. These are a collection of charts made by a group. Some packs have themes or “boss charts” with them.

Unfortunately, the Insane KSM charting scene is not very active, and new charts or packs are rarely released. The os/us table also rarely gets updated.

So why should I play Insane KSM?

The main idea of why people play it is that if you can master these unfair and difficult patterns, you should be able to play everything in the base game with ease. Essentially, Insane KSM can be for people who want to push their skill ceiling higher than the base game allows.

It can also be for people who feel like they have run out of charts to play in their skill level. If you feel like you are just playing the same things over and over, it might be nice to try new charts.

Also, not all charts are bad, unfair, or overly difficult. There are a lot of charts in these packs, with most of them just being normal charts people made. A good amount of charts do not have illegals and act as a normal Voltex chart.

os/us Scale

Insane KSM uses a different scale than the 1-20 scale present in Sound Voltex. These are the os/us scales. The official table for how this translates to SDVX difficulty is this:

Levelos/us
1-16us1-16~
17us17-, us17, us17+
18us18-, us18, us18+
19os0-2~
20os3~
20+os4-16

This is the table that is shown in the excel sheet for Insane KSM . These are not exacts though, only estimates to difficulty.

In v5.0 of the Insane KSM table, everything below us18- was removed. but still exist in the v3.0-4.0 table.

Charts are split between Normal and Unique charts. Unique charts are marked with a * at the end. For example, an os 3 unique would be marked as os3*. Unique charts are “Charts that have gimmicks and or elements that are not suitable for the table, but are well worth playing”.

There exist os0** and us0** charts that are even more gimmicky and individual differences. These often have lots of illegal patterns, weird patterns, focus on one very specific skill set, or just a gimmick/joke chart.

The majority of charts from all packs don’t make it onto the os/us table. Only a select few from every pack get graded and make it onto the table. This doesn’t mean you shouldn’t play these charts, as those can be very good charts as well.

For all the os/us charts, see the 難易度表 sheet on the Insane KSM Google Sheet .

The os/us scale is commonly refer to as Overshoot for os and Undershoot for us. It is unknown where the term “Overshoot” and “Undershoot” came from but this is technically wrong. The os or オーエス difficulty table was made “ぼ～ん” (bōn). “ぼーん” derives from the hiragana transcription for bone, and os itself derives from os in French and Latin  which means bone. Overshoot actaully refers to a pandemic outbreak  in Japanese.

In the english community, it is commonly called Overshoot and Undershoot though.

Undershoot or us

us are below os and are easier than os. These are often charts that are good for starting.

The us scale is from us0- - us18+ with us18+ being the hardest. Unlike os, us charts are divided into 3 groups, -, nothing, or +. These markers represent difficulty. A chart marked at us18- is easier than a chart marked as us18 or us18+.

Overshoot or os

os are above us and are harder. This is where more of the crazy charting comes into play.

The os scale is from os0-os16 with os16 being the hardest. Most of the charts are between os0-os8. As you go higher up, there are fewer charts for each respective os. There are actually no os15 charts and only one os14 and four os16.

How do I play?

To get started, you must first choose what simulator you want to use. The recommended for Insane KSM is K-Shoot Mania. This is for a few reasons:

  • KSM has subfolder support. A lot of packs have multiple folders to organize their charts
  • Some charts are KSM only, breaking or not working on USC
  • There is an Insane KSM tool to sort your os/us clears and give you recommendations. This only works with KSM as USC stores your scores in your maps.db
  • A lot of charts use weird camera work that was built for KSM. USC camera works differently so depending on the chart, it can make charts easier or more difficult to read depending on the camera
  • KSM has effects that only work on KSM

That is to say that you can use USC if you prefer. The same advantages that USC has over KSM still apply. Just for Insane KSM, there is more of a reason to use KSM over USC. For more information about simulator differences, see simulators page

Once you decide what simulator you want to use you can now download packs.

Downloading Packs

If you only care about os charts, you can download all os charts from this Google Drive.  This drive has every single os0 - os16 chart that is officially on the v5.0 sheet. It does not include all the extra charts from these packs. This also works as a way to sort os charts by folder for USC.

For *most Insane KSM charts till 2024/12:

Packs that arent included are

  • RanKirby’s Additional Chart Collection 2021/11

For all pack individually, you can find them in the パッケージ集 sheet of the Google Sheet. 

Insane KSM Tool

If you play on KSM, there is a tool that goes with the os/us scale and can be used to:

  • Sort your os/us clears,
  • Give recommendations for what to play
  • A “level” system that works as a way of tracking your skill
  • Create .fav based on all the os files you have.

This tool is in Japanese only, but there is a rough translation below.

You can download this here . Press the small ダウンロード button and then Download Now.

Extract this folder to where you want and run KSM Score Tool.exe. If it is your first time running it, you will have to point it to your scores. This will be /your KSM folder/score/PLAYER/. If you have renamed your profile in KSM, PLAYER will be replaced with what you named yourself. It will then process all your scores.

After it’s finish you will be brought to the main screen which displays your profile. To view more, click メニュー (menu) at the top left.

KSM tool menu
  • ムイページ. My Page. The default page that shows your Name, Recommend, Class, and License
  • 全スコアデータ. All your score data. This doesn’t work and will crash as it is in development.
  • 統計. Statistics. This will show you your stats on a specific range of difficulties.
  • リコメンド対象. Recommended targets. This will show you recommendations for charts you can upscore.
  • ターゲットスコア. Target Scores. This doesn’t work and will crash as it is in development.
  • favファイル生成. .fav folder creation. This creates a .fav that organizes all the charts you have into the os/us folders for KSM. These folders are then shown in KSM. Pressing this will bring up a confirmation window in which you can press はい to continue.
  • License生成. License course creations. This will create the courses for your “License”. This is similar to Skill Analyzer. Pressing this will bring up a confirmation window in which you can press はい to continue.

At the very minimum, it is recommended to create the .fav to sort all your os/us in KSM.

The other option next to メニュー is オプシュン (options).

KSM tool options
  • 楽曲名とパッケージ名の全表示/一部表示切替 Toggle full/partial display of songs and packs. This makes it so it shows the whole song or pack name for every chart that is shown. Example shown below
  • フオントの変更 Font options. Change the font

Example of toggle full/partial display

Toggle difference

While it says this tool is “in development” it has been a while since it has gotten an update.

Upon relaunching the tool after closing, it will ask you first if you want to change your directory to your score folder. You can press はい to continue, or いいえ to change your directory. It will then ask if you want to reprocess your scores. You can press はい to continue, or いいえ to reprocess your scores.

Is there any other charts?

While the Insane KSM charting scene is not as active anymore, you can find a lot of custom charts in the style of os on Nautica.  Nautica is where users upload their custom charts. While most charts are normal, there exist os-style charts here as well.

Charters that often create harder charts are:

This doesn’t list all charters or charts. There many more good charts on Nautica that you can find as well.

References and Further Information

Basic and Premium Course, Rivals, Downloading your data, Etc.Maintenance and Downtime