I noticed this in my fish tank one of my two bettas would bully all the platys in my tank but my more relaxed one is getting his find nipped but the one who would attack the other fish controlled the tank
I fall into the bad experience with male Betta's in a community tank, I introduced him to it and within 10 seconds he lunged towards one of my glass fish and the 2 angel fish immediately turned towards him and cornered him. I managed to scoop him out right away and prevented a war.