According to legend, Kralkatorrik is one of the slumbering elder dragons, who's been snoozing in the middle of Grothmar Wardowns in the Charr Homelands since... before anyone remembers when!
Rotty, though, informs me that Kralkatorrik is the Elder Rot Wallow, far superior to dragons. He cites his own adorably spiny back as a reference. Gotta admit, there is a resemblance...