EB II 2.2r Weird Gameplay

I am playing a campaign with the Pritanoi. I observed on several occasions a weird behavior by the game. My army besieges a town with only 2 units as a garrison. At the start of the next turn, however, the town garrison has swelled to 12 units. How is this possible? I am sure my army was besieging the town, because it was preparing ladders and rams.

I was besieging the Areuakoi capital Sekeiza.

Has anyone experienced the same? Is it a bug?

I remember that there was something somewhat similar in EB I with rebel armies. However, on the above occasion, the town was not owned by the rebels.

That is the garrison script. It only applies to certain settlements. It represents the people of the land rallying to support themselves against your siege (before you laid siege...though we can only apply it after). It is there because the AI can be bad at leaving garrisons and it's unreasonable that a whole chunk of land is going to be guarded only by two units.

Yep, it's the Selective Garrison Script. Spawns up to 10, mostly levy-grade units in the factional capitals (when held by that faction) and some selected "Rebel capitals" if they're besieged. Only fires once every 10 turns. It's to cover the AI's woeful inability to appropriately garrison its capitals.

By the way, at least in my case, the ai was guarding the settlement. They had two units inside, because the previous turn I won a battle where they had one full stack outside the capital and one stack inside. The two units were the survivors from the battle. Still that extra challenge is cool.

Thank you! It is a good way to compensate ai. Thumbs up!