Wagtail
Horse servant
FWIW I do not think that horses can talk to ACs. Goodness me, even humans do not understand most foreign languages, and so how could a horse understand ours? They of course learn various words that we teach them in the course of their training. But they do not 'talk' in the same way that we do. However, as someone else said, they are very emotionally intelligent, and excellent at reading body language and sensing mood etc. My personal belief is that many animals, and in particular horses, communicate on a level that we do not yet fully understand. Some of that may be described as psychic, but I believe that we all have a sixth sense. Some far more than others (such as the genuine ACs). I don't believe it is anything supernatural, so nothing like in the same class as ghosts (though I have a theory about them too which I won't go into here). I believe sixth sense is scientific fact, and that one day we will understand it.