Idoubt you're supposed to be able to equip armor and weapons on a Ophidium, and i'm pretty sure we shouldn't be able to put them on a horse.
BUT since we can do that, I'm glad that the way they attempt to ride the horse, is to be strapped to the undercarriage!
edit: they can't actually be trained, just designed. OK it's just a [bug] after all not [kinda awesome] 
