I couldn't find a good detailed tutorial for what I wanted to do, and I think one would of reduced the time I spent figuring things out considerably. So, I've decided to make a tutorial myself so you all can benefit from my tinkering. Now I won't pretend to be an expert. I just found out about Kenshi last week and didn't start trying to mod the game until a few days ago.
The mod includes
Nodachi (a large version of the katana)
Muramasa Steel (A new weapon manufactuerer, providing the best weapons for the highest cost)
Tweaks to Globals to make combat look better/faster (Less standing around)
Ronin Faction (A faction of wandering ronins who will kill you.)
6 Different kinds of Ronins in 18 different squads with various sizes.
(Weak, Drunk, Angry, Strong, Heroic, and Legendary)
If you see a Legendary Ronin, or the Ronin army, you should run away. (Unless your zatoichi of course.)
Mediafire:
http://www.mediafire.com/?zkvv43spg1ohwfz
Dropbox:
http://db.tt/aGy0c9zg
Now, lets go through set-by-step how to make this mod.
Note: I'm sorry but the images in the tutorial got cut off on the forums. Some of them you can't see the relevant information. Right click the image and hit view and it should take you to the full image. Sorry about that, I'm not great with forum images and the like.
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Step 1) Opening the Game Editor

You'll need to navigate to the directory you installed Kenshi in. The default is C:\Kenshi\
So unless you changed it that's were you'll need to go.
You can ignore most of the files here, although later you will go into the data folder and edit the .cfg.
For now though, double click 'forgotten construction set' to open the editor.
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Step 2) Creating a New Mod file
Now that you've gotten the construction set open, DON'T PANIC!
With that out of the way, we need to create a new mod for our changes to go into. That way we aren't overwriting the main game data with our changes (which is bad.)

As you can see, you'll need to click that little button at the top left. It will bring up a window that you can name your mod and save it.

I picked "ronin" as the name because, that is what this mod does. It helps to be descriptive with your mod name so you can know what it does. (You can have multiple mods as well and the ones lower in the order will overwrite ones higher so it can help when deciding how to order them as well.)
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Step 3) Loading Game Data
Now that you've created your mod, it is time to get started editing right? STOP RIGHT THERE!
First we have to open the game data! To do that, we need to load it.


You'll need to make sure gamedata is checkmarked and then check ronin.mod in the lower area. I'm not sure what vurt.mod (vurt the foliage guy?) is so leave it alone.
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Step 4) Creating A New Weapon & Manufacturer
Now, it is time to get started editing! Woo!
First things first, though, take a look on the left at the game Data tree. You can see quite a few things here and some with little + signs, that means they have stuff stored under them. If you hit the plus it will open it up and you can find...you got it, more stuff!
Now, let's make a new weapon.

Hit the + sign beside items, and then the + sign beside weapons. That will open up the items so you can see everything under that.
Now, you'll want to click on Weapons (mesh) and it will show you a list of all the weapon meshes in the game. Now, we want to make a nodachi, essentially a giant katana. It is a lot easier to duplicate an existing entry and modify it than to make a new one from scratch. So right click katana and duplicate it.
A new entry will appear, lovingly named: 'katana - copy' You will want to double click that to open it up.

First thing we will want to change is the name - Change that to Nodachi
Second we should change the damage, getting chopped by a nodachi should hurt a lot more than a katana. So bump up the cut damage multiplier to 1.5
Third, increase the size of the sword in the inventory! I bumped it up to 2 tall and 8 wide, since this is a big sword! Also bump up the weight to 10, such a big sword is a lot heavier than a katana! Also the value, I bumped that up to 1500, which means it is a lot more valuable than a katana is.
Fourth, Change the description to something relevant. Also the weapon length. I increased it to 26. I am not totally sure how that effects the weapon in-game, but it seems a good idea to increase it.
Fifth, The scale. Essentially the nodachi will be the exact same as a katana right now, that is where scale comes into play. Bump up the overall scale to 1.2 and the scale length to 1.4
It won't look perfect, but then I'm no artist.
That is it for the Nodachi, close the window and time to make a new manufacturer.

Click on Weapon Manufacturers in the Data Tree. You'll get a list of manufacturers.
Just like the nodachi, duplicating is easier than starting a new entry from scratch. Duplicate Edge Walkers and then double click it.

First you'll want to change the name of the manufacturer, in this case "Muramasa Steel"
Next, the description, the item level, and the price modifier. The price modifier will multiply the value of the weapon by this much to get the final value. I don't know what item level does, shows how good the items are, maybe. I've no idea how it is used though. I put the price for Muramasa Steel up to 5.0x this means any weapon from Muramasa will be 5 times more valuable than normal. Not too bad for the best quality money can buy!
Third, The stats modifiers. These will change the amount of damage weapons from this manufacturer do. It can also effect the weight. I bumped Muramasa Steel up to 1.8 damage and 1.2 weight to reflect how good the weapons Muramasa puts out are.
Fourth, we have weapon models and weapon types. The models have to do with the texture applied to the weapons somehow, I haven't figured out how that works yet sadly. Of interest to us is the weapon types. Each weapon this manufacturer can produce is listed here. We need to add our nodachi to the list!

You'll need to select weapon types from the dropdown box and then hit Add. This will bring up a new box asking you what kind of weapon type you want to add. Select our Nodachi from the list and hit ok!
The nodachi will be added to the list and that will be it for our weapon editing!
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Step 5) Adding Characters
So we have a nodachi and a new weapon company, now we need to get on to creating the actual Ronins!
The first step for that is actually creating the characters for our ronin faction.

Select Characters from the Data tree and make a duplicate of the starving bandit (once again duplicating is much easier than starting a new entry from scratch!)

Open that up and you'll be greeted by the character's information. On the left you'll want to change the name to "Weak Ronin"
Also of note on the left is the stats randomize. This is how much the stats will be randomized for each character. It can add or subtract up to this amount (so make sure it is less than his stats!)
The bulk of information for characters however is on the right.
First we have the dropdown box and add button. These are essential for adding new entries to the character's information.
Second is his clothing. Right now he only has shorts.
Third is his stats. There is a template for various levels of stats lists 5, 10, 15, 20, 30, 40, 50, 60 etc.
Fourth is the weapon level, this determines the manufacturer of the weapon the character has.
Fifth, we have his actual weapon. Note there are three entries but the Katana has a 1 by it. The ones with 0 won't show up.
Let's give him a jacket to wear.

From the dropdown pick clothing, then hit add. A new window pops up, find Jacket in that big list. Select it and hit OK.
Go ahead and add a straw hat, and some wood sandals as well.
After that make sure you change each of the new entries value to 1. If they are 0 they won't be created.
Now we need to change his stats, even a weak ronin won't be at level 5 skills.

Right click the number 5 under stats and hit remove from list.

Now, from the dropdown pick stats, and hit add. Select 15 from the list.
That is it. You've made a new character! Pat yourself on the back. Close the window.
Now you can fill your faction full of weak ronins, they will all wear the same thing and have about the same skill though.
Or...
You can make more entries each one slightly different. I've gone ahead and made 8 different ronins, each a little stronger than the last. I gave the strongest and last version of the ronin our nodachi from Muramasa Steel.

You can go ahead and do the same, or skip that part for now.
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Step 6) Creating Divisions (groups!)
Now we have a merry cast of actors, but before we can get them into the game we need to put them into groups!

Hit the plus by faction, and then click on Divisions. Find the bandit mob group and duplicate it.

Looks pretty familiar to the character window right? On the left, change the name and you can choose to randomize the group size.
On the right we have:
1) The familiar drop-down box.
2)AI Goals Not sure about this one, the groups overall orders?
3)Group Leader The boss of the group, everyone in the group will follow this guy.
4)Group Leader AI Goal The bosses orders, basically what he does. In this case, he Patrols around the desert.
5)Squad These are the characters in the group.
6)Squad AI Goals This is what the characters in the group do, right now they follow the leader!
Go ahead and remove the leader and the squad members. Then you can use the drop-down box to add a new leader (from a list of all the characters! yours will be near the bottom of the list) and new squad members.
I went ahead and added 18 different squads, 4 tiers (Weaks led by Drunks, Drunks led by Angrys, Angrys led by Strongs, and Strongs led by Heroics.) and two squads led by a Legendary (One leading several heroics and one leading a huge group of ronins of all classes.)
You don't have to add so many, but variety is the spice of life!

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Step 7) Creating a faction (and shoving our groups into it!)
Now that we have our ronins all nicely put into groups we need to put them in a faction.

Duplicate the Starving bandit faction, and lets get started!

Things should start to be looking familiar now right? On the left you should change the name to "Wandering Ronins"
First note the default relations. This tells them that any non-specificed relation will be at this level. -50 is hostile and 0 is neutral. We want the ronins to kick your ass, so leave it at -50.
Second we have the AI Goals again, I believe this is the main goal of the faction, just leave it for now.
Third we have the faction color. We don't want out ronins to be yellow like those ugly dust bandits. Remove it from the list and set it (with the drop-down box choose color and add) to something better, like super black.
Fourth we have default squad. I'm not sure about the difference between squad and default squad is, but the other factions seem to put their smallest weakest group as default, so I have done the same. I added WeakRonin1 as the default squad.
Fifth we have squad. This is where you put each of the ronin groups we made into the faction. You'll have to add each group to this.

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Step 8) Adding the groups to spawn
Now we have the characters in groups, the groups in a faction, they should be all over the desert right? Not so, we must add them to the spawnlist first.

Hit + beside Biomes and click on Spawn Areas
The only entries so far are:
UC WEST
UC EAST
and Northern Desert
You'll want to double click UC WEST first. You'll eventually edit them all though.

On the left of interest is the Spawn Max and Spawn Min, these determine the maximum/min spawn in the area. I believe that is how many can spawn per area and each spawn has lots of areas. Putting it too high will cause a ton of lag, however I raised it up to 5 and the performance on my machine seems to be fine. The default is 2.
(Also of note is the population count, I read on the forums in a post by somebody that raising this prevents die-out over a long period in games, although I haven't tested it myself.)
Finally on the right of the box is where most of the work will be done. You'll need to open your friend, Mr. Drop-down box and choose spawns and add each of our groups to the list. Once they are all there then you can change their spawn chance. As explained by someone else on the forum each number gives that group a stone in the bag, and then one stone is pulled out of the bag, the group that had that stone gets spawned. Basic ratios.
Since we have added so many groups, I gave each one only one chance to spawn. That gives the ronins the equivalent of 18 points to spawn.
You'll have to repeat all this for each area. Or just leave them in one area if you don't want them to spawn in the different places. (Thats a good idea one could make different difficulty zones for each area.)
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Step 9) Global Settings and Tweaking
Now our ronins are in the game, really! We aren't done yet though, lets do a few tweaks to the global settings.

There are a lot of options here, and they can change things drasticly or even cause the game to crash, so be careful while changing these!

We'll make four tweaks, that I found I liked. They make combat look a bit better I think.
First thing we will change is 'max num attack slots' this setting as described by the editor is how many people can be swinging at one guy at the same time. I raised this to four from two. When I raised it to 6, the game started to crash, so I wouldn't recommend going higher than four.
Second thing we will change is the 'damage multiplier' this is a overall setting and will effect the amount of damage done to characters. We need to lower it because of other settings we are about to change. I went ahead and lowered it from 0.75 to 0.50
Third is 'animation blend rate' this controls how fast our guys fight in combat. Overall it results in a whole lot less 'standing around' and makes combat look a good bit better. Default is 3, I doubled it to 6. This is why we lowered the damage. People will be getting hit a lot more. If you want to make combat a lot more fast paced though you can leave the damage multiplier alone and fights will be over one way or another quite quick.
Fourth is 'exp gain multiplier' we need to lower this because of the quicker combat speed from 'animation blend rate' I lowered it from 3 to 2. So experience will be gained 2/3 as fast.
Thats it for our tweaks. However, you should feel free to look at each of the settings and play around with them! You can really change the way combat works with these, maybe even for the better!
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Step 10) Mod.cfg and The End
Before our mod will show up ingame we need to add it to the mod.cfg file.

The file is located in the data folder inside your Kenshi directory.
Open it with notepad and you'll be greeted with a blank file. You need to add the name of your mod with .mod at the end. So
ronin.mod
in our case, unless you used a different name!

Make sure to remember to save the file before closing it.
Aaaand that is it. You've done it. You've completed your first mod! Congratulations!
Start the game up and go running around, you'll find the ronin roaming the sands with all the other bandits, ready to slice and dice you and anyone else that isn't a ronin!
Now that is it for this tutorial however there are a few things you could do!
1)Add the nodachi and Muramasa steel to the stores.
2)Add more types of ronins and add them to new groups.
3)Make a second ronin faction with a different color, call them "Law-abiding Ronins" and make their default relation 0 so they are friendly to the player and the police/armies.
Good luck! I hope this tutorial helps you with your first steps in modding Kenshi!
