"But no Esu, either! How that would irritate...her...if she even...still rages..."— Bul-Kathos(src)
Esu was drawn to the power and ferocity of the elements, and gained mastery over the powers of storm, earth, fire, and water through intense meditation.
Bul-Kathos regarded Esu as being somewhat prideful, that it would have irritated to her to know that she had been forgotten by humanity. He also had a dim view on her use of magic, stating that the Worldstone was sealed away "from those like Esu," who would have used its power to ravage Sanctuary. It may have been a moot point however, as by the Sin War, he pondered whether she was even still alive.
Ages after the time of the Ancients, Esu's followers would arise in the form of the Zann Esu Clan. In contrast to Bul-Kathos's assumptions, there is evidence that Esu may have still been alive by this point.
- The month of Esunar is possibly named after her.