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Jadawin's Unnatural Selection Ultimate (Updated for Omens of Destruction)

Updated Jadawin's Unnatural Selection Mod for WH3 because he's not updating it. I am not the original author of the mod and all credit goes to Jadawin for the mod, I just edited it a little bit to add the new factions that came with recent DLC. The following is from the original mod's description.

Overview
The popular mod from WH2 is back for WH3 Immortal Empires. With this mod you can apply a buff or debuff to almost every AI-controlled faction in the game that will increase their chances to do well against other AI, and also affect their economy, upkeep costs and other bonuses. Battles against the human player are unaffected.

Features
via the Mod Configuration Tool (MCT), you set buffs or debuffs to individual AI factions
these modifiers adjusts the faction's "faction potential", a value that determines their bonuses/cheats as well as their autoresolve odds against other AI factions (but not against the player)
the buffs can also be randomized to get a fresh and unpredictable campaign experience
setting a buff to -4 will kill the faction and remove them from the map
with the parameter for personality switch threshold you can give minor factions the personality of a major faction

Tips & Details
buff levels 1-3 should be enough to ensure that the buffed factions do much better
stronger buffs may lead to very unrealistic outcomes, like small garrisons wiping out full elite AI stacks
the settings for randomization can only be used on the first turn of a campaign, they have no effect afterwards
killing factions by setting them to -4 also only works on the first turn
if randomization is active, the buffs for eligible factions are set randomly according to your settings after the first turn, you can manually adjust individual faction buffs at any time afterwards
a few factions are not on the map on turn 1 (hordes), so they can't be killed or randomized, you can only set their buffs manually

Rewrite for patch 2.3
Although it looks the same and mostly still does the same thing, the mod works completely differently internally since the patch 2.3. Thanks to fellow modder Agemouk who made me aware of a post by a CA dev in a random Discord conversation where he described two undocumented functions, I now know how to manipulate the faction potential directly. So now the mod does that instead of going the more complicated and less effective way of applying stat bonuses to AI armies.

This also allows to effectively debuff factions instead of only buffing them.

A side effect however is that buffed factions will also generally have bigger AI cheats, so they will have more money and lower upkeep costs. If you buff a lot of hostile factions, you effectively raise the difficulty of your campaign. Conversely, if you debuffed every faction with -3 setting, you would effectively play on Easy even if you chose VH campaign difficulty. In a typical randomization setup, I'd recommend to distribute a mix of debuffs and buffs so that factions fall between -1 and +2.

Because debuffs now exist, the value to kill off a faction is no longer -1, but -4!

Compatibility
Savegame compatible: Yes
Multiplayer: Now that MCT supports MP, it may work
SFO, Radious: Yes
Other mods: Will conflict with any mod that adjusts faction potential via script

Troubleshooting
Before reporting issues, make sure that you have the current version of the mod. Steam quite often fails to actually pull the newest version after a mod has gotten an update. To make certain that you have the current version, unsub from the mod, then wait a few seconds. Steam will then delete the mod file from your hard drive. Then resub to the mod and Steam will download the current version to your hard drive.

Read before posting a comment
Make sure to use the newest MCT. The 0.9 beta is much better than the previous version that is now called "Legacy"
If you are a long-time user of this mod, you may think it doesn't work anymore because you don't see the effect on AI armies. That is not the case, in the current version there are no visible effects on anything, the mod still works. It affects the AI factions directly, so the effect is not visible except by the result, them being stronger and more successful