I think perhaps we're finally going to be able to put Chief, the paint, out in the pasture with the others. He seems to be finally learning to play "horse politics" properly. And he now knows where all the electric fence is located.
This video begins with Blue, Libby, and Chief, the new guy. We removed Tude at first, and Sassy is in the box stall recuperating.
The first horse to show ill will toward Chief was Libby, the baby of the bunch... my little sweetheart. After that performance, she comes to the camera as if to say, “Aren't you proud of me? Didn't I do good, chasing him off?”
When Tude is turned in with the others, he shows his true colors, and we find out Blue is equally a villain here. Obviously the two geldings like to gang up on the new guy.
This is all normal horse behavior. When Chief finally learns to keep his distance from the group, they'll gradually allow him closer until he's an accepted member of the herd.