So, you may have tried to give a non-teacher char a dual skill, only to notice that they cannot do the skill. This is because the dual skill intial "kick" must be added to the bac and bcm (also these chars need the bdm of a char with dual skill or the kick will always miss due to not having the hitbox)

Tools needed:
- dual_tool. You can find it in my tools thread in the Tools section.

Files needed:
- You need the XXX_PLAYER.bac and XXX_PLAYER.bcm of the char you want to add the skill too. Additionally, you need the XXX_PLAYER.bac and XXX_PLAYER.bcm of a char that has dual skill support. Probably any characte works, but you may want to use a character that you think is more or less "close" in size or whatever.

In the tutorial, I will use as example giving G17 dual skill support. I will use G18 files as "source".

Step 1
Copy G17_PLAYER.bac, G17_PLAYER.bcm, G18_PLAYER.bac, G18_PLAYER.bcm to the location where you extracted the exe. The G17* files will be modified, the G18 will be only in read mode.

Step 2
Run dual_skill.exe. It will ask you for the character WITHOUT dual skill support. Enter "G17" (without quotes).
It will now ask you for the character with dual skill support. Enter "G18" (without quotes).

That's it, the program will copy some data from G18 bac/bcm to G17 bac/bcm. Now with these bac and bcm, G17 can now do the "kick", but the kick will always miss.

Step 3
The character needs a bdm with duall skill support. I want to leave this clear: if the character doesn't have a bdm assigned in the cms, the character bdm will not load.
G17 is a case of character with no bdm (he has a bdm file, but it is not used because the bdm in the cms entry is empty)

Use genser or mugen attack tool to modify the cms. In genser, the bdm entry is called "STR_50" (I need to change that).
Use the one from android 18, so put "../G18/G18"

Alternatively, you may want to create a clone of the char with minimal files by using character creator, and give this clone the proper bac and bcm, and have the bdm pointint to G18.

Step 4
The character needs the dual skill assigned in the cus. Use genser or the mugen tools, or if you are creating a clone, the character creator.
It is worth to mention, that apparently you can use any dual skill, not necesarily the one from the char you copied the bac/bcm.

For the character to be able to use the skill, the following conditions must happen.
- If the character inits the dual attack: the other character must have same dual attack assigned or must be a real cac (cac2x2m don't count)
- If the other character inits the dual attack: the other charactrer must have exactly the same dual attack.

Considerations of other examples

Goku Black special case: the non-rose version of Goku Black can already uses dual skills because his bac, bcm and bdm entry point to Goku one. You only need to assign a dual skill for him.

The rose version, however, needs the bac and bcm changed with  the dual_tool, and his bdm changed. He has a bdm assigned in the cms, but that one will not work. Either copy the Goku bdm or change the cms to point to Goku bdm (i don't know if this has any side effect on Goku Black Rose, apparently he works just fine)

Bonus

As a bonus, I give you an android 17 clone with minimal files (reuses almost everything from original), in x2m format. Link.
Now, you can kill Future Gohan as it is due: