So I was trying to summon a horse with no AI so I could finally make the perfect sittable block. I tried a pig with no AI first and it did not move, but the saddle was still visible when I summoned it to be invisible. I then tried the horse, and the saddle became invisible when I summoned it that way, but it seems to move whenever you sit on it, whether it be saddled or if you are trying to tame the No AI horse.