Hi,
When I destroy some target enemy base biters from nearby bases' nests come to help - Ok. After target enemy base is destroyed, those helping biters start to attack my base - a few waves is ok (pheromone effect, free unlinked biters, retreat and attack), but they never ever stop coming wave after wave. Pollution cloud doesn't reach that base. No matter how far away that helping base is located from my territory biters are coming and coming. So it is an endless cycle: attack base-1, attract helping hand of base-2, destroy base-1, start destroying base-2 to prevent endless attacks from it, attract helping biters from base-3, base-2 destroyed, now biters from base-3 are permanently coming, so I have to clear base-3...
Is it biters behavior by design?

Do you have a save game?
The endless attacking is not by design.

Here it is
https://send.firefox.com/download/0b01d46a00b81de0/#tlH1H5BMBAGzkUMmJA0GHg
Two far away bases on the East are sending waves (size of waves depends on the count of nests as I understood) all the time since I destroyed their neighbour bases. I have save from another game too - in any game with Rampant mod I face this situation.
Rampant's MigrationAI and RaidingAI options don't change the behavior in any options state.

did you use anything special to destroy those spawners that were in the pollution on the East side of your base?

Rampant still thinks there are spawners on the east side of your base in the pollution cloud. It just so happens the spawners just outside the pollution cloud are close enough to be getting pulled into attack waves.

Nothing special was used - I destroyed the spawners bases in the East-Center and South-East corner with turrets creep (no fire was used - no manually created pollution source).
Later (after the moment this game save has been created) I destroyed the farther spawners base on the South-East where biters come from, and it triggered physical-protected faction biters in the third biters base (in the same South-East-East direction) to attack me. But after about 3-4 dozens of waves they suddenly stopped attacking me. While that huge biters base on East-Center attacks me for many-many hours till the moment pollution cloud really reaches them - then they all just come in enourmous wave (over 20 physical-protected and over 40 usual biters+spitters) and kill me.
That is really strange - sometimes 'helping hand' biters of neighbouring base stop attacking almost immediately after target base was destroyed and I removed my turrets. I can't understand what is different in those situations. I destroy bases the same way all the time (a few dozens of bullet turrets).

Also I noticed, that pollution cloud for Rampant doesn't need to touch spawners like in Vanilla. It just needs to be 1 chunk away from any spawner for that spawner and its family to start sending attacker waves (So factorio production statistics doesn't show any spawners to eat pollution while pollution-triggered attacks do happen). People in other forum thread noticed it too and use some special mod to get exact info about it.

The fix for this is enabling full map scanning that appears in the mod map settings. I thought that I had covered every way that spawners and worms could be removed from play, but it seems I'm missing some.

In the next update, the full map scanning will be enabled for new default.

I check for pollution around the spawners due to them consuming pollution, which causes the spawner to appear to the Rampant logic as a uncovered spawner when it really is.

What metrics are people wanting?

Unfortunately it didn't help. I see how this option changed the game - factorio uncovers all known chunks 'for free' on game save loading.
Anyway your mod is really great, I noticed how it progressed since last time I played (new features, no more 10Gb+ RAM consumption, etc). I was unable to find anything even close in terms of modifying enemies, making them interesting, less predictive, harder to clean up. It's very important for those players who play Factorio not only to build production chains and megabases, but to purge territories and destroy :-)
Thank you for that.

I check for pollution around the spawners due to them consuming pollution, which causes the spawner to appear to the Rampant logic as a uncovered spawner when it really is.

What metrics are people wanting?

https://mods.factorio.com/mod/Rampant/discussion/5c9b8856bc6a7d000b6ad9cb?quote=48
The last message from ptx0. I can't find how to make direct links to post in this forum.
For me it is good that Rampant makes biters angry even when pollution is only coming by, not over nest.
And for me changing evolution mechanics is probably the last solution to choose and only if I decide to attempt Rampant max tier 10.

Looks, like I was wrong! Full map scanning really helps! It was a pollution in neighbour chunk, that still triggered attacks. In vanilla factorio pollution is consumed when triggers attacks and polluted chunk is flickering with pollution in Map view - an easy hint of attack squad being prepared.

Glad you are liking the mod and the scanning fixed your problem.

If you have any feedback, please let me know.