Another expansion after Northrend was the addition of the Cataclysm. Cataclysm is the remapping of the original world of Azeroth. There were discussions that this is Blizzard's attempt on editorial, on global warming. The dragon represents our industrialization on the effects on the climate. In the maelstrom there are four realms, representing the elements of earth, water, fire, and air. The goal is to defeat the dragon named Deathwing.