Geleona is a dark-skinned enchantress who helped General Augustus Malevolyn to find Norrec, who had the Warlord of Blood's armour. She did a deal with Xazax, who was also looking for the armour, to help her and she would help him. Each of the three seeking the armour all wanted it for themselves, and only helped each other if they got something out of it themselves. Their story is described in Legacy of Blood.
Geleona is described as being a Sorceress, much like the Diablo II playable class. However, the nature of her magic is not the same as the Zann Esu clan, who are strictly elemental. Geleona's magic is much darker as she meddles with demons, is very seductively persuasive, and has a strange magical tent that is bigger on the inside than it is out, and contains many strange items. It's certain that she knew some spells that Norrec, possessed by Bartuc, knew; so she had some knowledge of the ancient Vizjerei magic.
Her life ended when she tracked Norrec (who was wearing the Armour) to the Arcane Sanctuary and seemed to help him. But, when the Sanctuary started falling apart, she foolishly tried to save herself by leaving Norrec to die. Norrec, possessed by the Armour, became enraged at his betrayal, and the Armour retaliated against her, casting a powerful spell at her. She tried to defend herself with her own spell, but she failed. The Armour's spell killed her.