Cloud and storm giants are the most powerful of the standard races of giant in the D&D rules, the two final rungs on the ladder of increasing humanoid power. There doesn't seem to be any specific inspiration for them, although giants are sometimes associated with the sky in myths and legends. They are also the most intelligent, and the most inclined to be helpful, rather than hostile.1E
Cloud giants are 18 feet (5.5 metres) tall, with bluish skin, and, unlike other giants, have what appear to be blunt, but greatly enlarged, canine teeth in the upper jaw. They aren't shown or described as wearing armour, so their skin must be equivalent to plate steel to explain their stated armour value. Most are of regular human intelligence (which is still smarter than most of the smaller giants), but a few are slightly better, and have limited skills with magic. They are said to have a particularly keen sense of smell, which is likely a nod to the cloud-dwelling giant in Jack and the Beanstalk, although they are otherwise quite different. They are also the first giants tall enough to have a stride that enables them to walk faster than humans, although still less than one might expect, given that they're about six times taller than we are.
