Ok, this is a new one to me, Skarf has a rider, you can target both, but at this point you can't attack or make the rider attack you, shot him with everything I had and he just keeps walking around, Skarf doesn't even attack when you shoot the rider. So here is what I did, target Skarf, Shot a Freeze Trap, tamed him, as soon as he's tamed, the rider jumps off and Skarf starts fighting him, makes it tough, he's not fed, and not trained

So chain cast heal pet, then open up the train window

Trained him, kept meding pet, Woot Success.
