My son shot a buck last year with a crossbow. Right behind the shoulder. We found the buck, bedded in a small depression in the ground. There was blood all over its chest and its head was drooping like a drunk about to pass out. He walked around to get a better angle for a finishing shot and it bolted. We never found that buck. We looked for hours that afternoon and into the night and all day the next day. Can't explain it. But, if we would have backed out, he would be dead in the depression.