When Hexbear federated, its users were "excited to dunk" on people again. Their copious use of visual memes, including a picture of pig testicles covered in excrement, stretched threads. They are also a big community, which means when they pile into a thread it looks like brigading.
I don't think it looks like brigading. It is brigading.
I defederated from them for a while, when they were really just jumping into everything and brigading anything that didn't meet their (quite extreme tbh) views.
But I removed them from the defed list and haven't seen anything so bad in a while. So, I think they've calmed a bit.