My horse (Dreamunity) has twice now lost a shoe off of the same foot. Other shoes were at 10 damage the first time a shoe went missing, and other shoes were at 3 damage this last time it went missing. I noticed the first time that a shoe was missing right before the Black Dragon fight on Deliverance, replaced the shoe and then continually did upkeep on the shoes to make sure it didn't disappear again. After about a week and a half and quite a few runs out of town I was preparing to repair and change her equipment. My friend bought me a set of Rare horseshoes as a gift and as I was about to put them on, I noticed the same shoe was missing (The Left Hoof). After repairing all of her shoes and saddle I moved the equipment to a different horse. The only people that have access to the horse are myself and my village (all are people I know IRL). I've asked and they say that they aren't messing with me.