Factorio Forums

Noticed a strange thing when testing new biter behaviour post 0.17.70. If I make a large horde of small biters (50ish) and attract them to my player they close in on me and after a few seconds of being really compact they shoot off away from me to just wonder around. The player is wearing lots of shields so effectively invulnerable from small biters. After 30-45 seconds almost all biters have shot off and they then all close back in again. The repulsed biters look to be the ones whose collision boxes overlap or are too close to one another.

https://gfycat.com/diligentnaturalchimneyswift

Test setup:
- Player has mk2 armor, 4 reactors and 9 shields
- place a lot of small biters in map editor
- walk near them so they agro on me

This is a side effect of them not-colliding,

They are able to 'move' from their point of view, but the separation force pushes them out,
So then they realize they are not really getting to the unit, and so there is no point trying to get to him, so they change to fleeing behavior.

I would say this isn't worth looking into, and move it to minor issues

But I will leave decisions to another

I wondered (not tested) if this behaviour would increase UPS usage through unit command state changes, pathing requests to flee and then return when next triggered, ect.

I.e. multiple waves hitting turrets sorrounded by wall. Would take small biters a while to chew through the wall layers and thus the "spare" biters would be doing this activity.