So I've been wanting to figure this out for a few days now, and finally got the chance to sit down and stare at the msg files for a couple of hours. This is a follow up to
The Mad Titan's "
How to change main charactor/skill/costume names". If you are looking to simple change letters around and rename something without the use of adding addtional characters to the name of the skill/clothing/character, then start with his tutorial. However, if you want to add additional characters to a skill, clothing or character for example say, Super Saiyan to Super Saiyan God or Super Saiyan God Super Saiyan, then this is the tutorial for you.
Normally changing the name of an item/skill to something longer will completely screw up all of the item's and skills that follow it. But only those that are below it. This is because the file containing the name of the item/skill uses an offset telling the game where the beginning of the name is and where the beginning of the next one is. Let's have a look at Super Kamehameha for example.
Scrolling down until we see ...S.u.p.e.r. .K.a.m.e.h.a.m.e.h.a... we can see that the first letter, "S" begins at the offset 131C. You can even place your mouse cursor just before the "S" and see the hexadecimal value of 53. You can look at the bottom left of HxD (the hex editor I'm using in the screenshot) and confirm that it is at the offset 131C. With that in mind, let's scroll up and see if we can find this offset.
Some of you, if you've edited your skills, aura, etc, before may already know that the offset bytes are switched around. Instead of typing in 13 88 as shown by some skill editing tutorials, you would type it reversed like shown in the Skill Editor ID's list on this forum, or 88 13. Here we are not looking for 13 1C, but instead 1C 13. Which we can find here higher up in the hex editor. This tells the game where the name of the first ultimate in the list is found. If you look right below it you will see a hex value of 3E 13. If Super Kamehameha is 13 1C, then the name of the skill right below it, Super Saiyan, must be the 13 3E offset.
And whaddya know, it is.
So, if you change the name of something, and it is longer than the name of the original, this will cause your bytes to completely screw up the game when it checks higher up in the msg files for the offset of where the name of the skill begins and it will be wrong.
What you could do, and the first method I used when trying this (like a dumbass), would be to continue to add the amount of bytes you need to type all of the characters you need place the 3 bytes of 00 00 00 (or ... as they show up at the end of a name) and remember how many bytes you added. Take that number of bytes and increase the offset of each skill name by that specific amount. If you change Super Saiyan to Super Saiyan God, that's "_.G.o.d.", or 8 extra bytes. You would then have to add 8 to each hexadecimal value to the offset of each skill that comes after Super Saiyan. Super Saiyan 2's offset of 1358 would be increased by 8, or 1360. Super Saiyan 3's offset of 1376 would be increased by 8, or 137E. And you would have to go through and add 8 to each offset for every skill...and that's like 5 minutes of tedious crap. Or a very long ass time if you even thought about doing that with the special (proper_noun_skill_spa_name_en) skills.
Instead, what we're going to do in this tutorial is look at how the end of the file is done, add our new name for the skill to the end of the file, and change it to the offset of the new name we want to give it.
Looking at the bottom we can see the skill name Emperor's Death Beam. (And also Super Galick Gun above that, god I cant wait to have my favorite beam attack as an ultimate :3) This follows the exact same pattern as all of the rest of them ending with 3 periods (00 00 00 or ...).
All you have to do is follow this same format and add your new skill name to the bottom of the list like this:
But, that wont do much good if we don't tell the game where in the file to look for the name we want to give it. So look at where the first letter "S" starts and its offset. I placed my cursor infront of the "S", and as you can see, the offset shown in the bottom right corner is 1D9E. If we want to set this as the name for Super Saiyan, we go up to the corresponding line with the offset I mentioned before (13 3E).
All we have to do now is change this offset to the one we added with the new name for the skill we want.
After that all you have to do is save the file, copy it back into your data2root folder, and repack into data2.cpk. Like colorable clothing however, I cannot guarantee it will always work like this. I believe I tried with datap2 earlier and wouldn't work, because Super Saiyan is part of the base game not DLC. For DLC Pack content, you may have to instead add this to your corresponding datap#.cpk file.