Real Dragons have lot of hit points.
Real Dragons, if they are intelligent, can use items in their hoard. Real Dragons wear a Ring of Protection on one claw and a Ring of Vampiric Regeneration on another claw. Real Magic-Using Dragons have a Rod of Absorption strapped to their forearm. Real Magic-using Dragons memorize mean, nasty, useful spells. Real Intelligent Dragons have plans set up to blitz would-be dragon hunters.