Version 4.0 Update 2
Difficulty and balance changes. The vassal opinion modifier now defaults to -10. AI war declaration chance has been doubled, making them more aggressive.

Version 4.0 Update 1
Reworked Civil Wars, Oathbreakers, Indirect Vassals, Bannermen, and Vassal Bannermen. Improved AI army behavior, UI notifications, and fixed all reported issues.

Version 3.2 Update 8
Calling the banners now has a delay. Each vassal will take a variable amount of time before responding to your call to arms.

Version 3.2 Update 7
Various bug fixes and general changes. Removed some base game overrides for certain triggers and effects. Several files have also been deleted, since the changes are no longer needed.

Version 3.2 Update 6
Added support for the Khans of the Steppe DLC.

Vassals who would lose or gain a title as a result of a war can now call their own banners to assist their liege.

Players who choose to remain neutral when called to arms will now become Oathbreakers if the bannermen feature is enabled.

Added a new game rule to allow Kingdom-tier vassals and Duchy-tier vassals to call their bannermen to war.

Changed the AI interval for the "Call the Banners" decision from 30 months to 12 months, so they do it more consistently.

Version 3.2 Update 5a
Fixed a couple of small issues with the new Bannermen feature.

Version 3.2 Update 5
The Bannermen feature has been completely reworked. When enabled, vassals provide 50% fewer levies but are obligated to join their liege when called to war, otherwise they are branded as oathbreakers, a punishable offense.

Added a new decision "Call the Banners" which can be used after a war begins. War participants can call their own banners as well under some circumstances (like a civil war).

Added a new notification "Vassal Breaks Oath" which is dispatched if a vassal refuses a call to arms and their liege has absolute crown authority or if the bannermen obligations feature is enabled.

Decisions to call vassals have been moved into the "Major Decisions" category.

Several adjustments were made to the AI to improve their war declaration logic.

New options for "Levy Size" and "Garrison Size" were added to allow you to reduce levies even further.

Modified some elements in the vassal participation UI for clarity.

Version 3.2 Update 4
AI war stance behaviors have been updated to account for the latest patch.

War declaration UI will now correctly display the total army count for both sides.

Several game rules can now be disabled again.

Version 3.2 Update 3
Slower MAA Reinforcement Rate is now disabled by default, but it'll apply a 50% reduction instead of 25%. You can enable this again in the interactive_main_defines.txt file.

Vassal Opinion now applies a fellow vassal opinion reduction in addition to the direct vassal opinion reduction, which incentives more internal conflicts.

Players will no longer be given the option to side with populist uprisings.

Version 3.2 Update 2
Crown Authority - At absolute crown authority, vassals who refuse a call to arms are considered oathbreakers, a punishable offense.

Vassal Opinion - All characters receive a modifier of -10 to -50 vassal opinion, making their realms more instable.

Vassals who join an external war can now be forced to leave if they are captured in battle by the opposing side.

Made some improvements to the War AI priorities so they focus more on battles.

Imprisoned vassals will no longer side with the rebels at the start of a civil war, and will remain neutral instead.

Combat advantage and adventurer limit are now controlled by game rules.