The horse had shocked Sam but when he was first being knocked down his brain caught up with him. Several, several past bar fights had taught him to think on his feet, plus the improvisation any musician knows how to use.

 His arms found themselves around the horses neck and he jumped out of the way, only to find himself very acrobatically sat on top of the horse. The horse protested for a moment but Sam's voice started a low hum and he instantly charmed the magic of life in the horse, as he normally did to horses to screw with their owners. The big guy stamped his hooves for a moment before the horse knelt down and began to fall asleep from the lullaby Sam was resounding in his ear.

Sam doubted anyone else could tell he was singing with how softly he was doing it. In the meantime, he hugged the horse and waited for the guy in the stone circle to speak again, he seemed to be a leader figure here.