I did a significant change on how raids work during "pristine ruins" event, so I need to draw your attention if you come to complain about that.
First of all, it can be toggled off. There is a switch in mod options, it is called "Use new raids system for events".
Now about the nature of the change. I was not satisfied with how events are undalanced and could not come up with a good way to make it harder. Adding proportionally more enemies could make it cumbersome or even unplayable for weaker machines, while limiting ruins wealths kills the concept of the mod itself (especially given there is no reliable way to reduce wealth in a sensible way because of specifics of how rimworld economics "works")
But I think I found a solution. Now, besides regular large raids, there will be small groups of enemies constantly entering the map. Enemies inflow is proportional to remaining wealth, which means the longer you stay the less frequent and smaller groups you get. But for large and wealthy ruins you can get as much as several groups of 3-5 people per minute. To avoid distraction and permanent raid sirens, those groups enter the map silently. Watch out for them. If you think you're done with all the enemies and now can loot freely - beware, it's no more the case. You'll need a dedicated group of people to defend your looters from those small groups. I hope it will bring some fresh air to the mod :)
Groups size and frequency are also affected by event difficulty slider in the mod settings.

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