So as of the latest update I summoned five catfish in various locales where I thought the land could use the clensing of'the river god'.
Out of all five fish, three merrily swam in the air endlessly. I like to think they achieved zen.
The fourth one went right to the aggroing...after it had been attacked. From what I saw the fish only attack people who have attacked a fish from last reset. Any subsequent summons seem to hate that one person. As seen in fish five who immediately airswam towards them.
Also odd in the behavior, fish four attacked anything near it, even those who didnt attack it. Fish five only attacked people who aided in the slaying of the fourth river god.