Camel Spiders. Period. I had nightmares of them when I came back to the point that I was losing a lot of sleep. Just thinking about being over there again and in their lair makes me cringe. The food sucks, having rockets and mortars landing all around is no fun, the weather is terrible, you cannot trust anyone, bathroom facilities are horrid, etc. but all of that pales in comparison to the wicked, demonic, hell-spawned little critters called Camel Spiders.