Baldinar Le Mudias was originally the Prime Minister of Kounat responsible for the kingdom's destruction. He would be known as Ashtaroth in the original game.
He was encountered in person in Grand Chase Dimensional Chaser and was fought as a boss later on.
Many years prior to the game's events, Baldinar obtained the Klara Libri, a book containing the secrets of the world. He followed the book's instructions and created the Soul Stone, however, it was too late when he realized that it can only be controlled by the Kounat Royal Family, who could withstand the Geas imposed upon them by the gods. The Aernas Hammer, powered by the Soul Stone, went haywire and destroyed the entire kingdom, leaving Mari as the only living Celestial. The destruction inadvertently created a war between elves and dwarves on the Archimedia continent, as the two sides had blamed each other for the incident ever since.
Even after several hundreds of years, Baldinar had survived as an astral form due to the effects of the Soul Stone. Soon, he snuck deep in Xenia when he realized that the Deity Orbs held by the six gods are pieces of the stone he had created. Due to the demonic essence that had been spread by him, numerous creatures evolved into monsters and the gods started to lose their sanity. Taking advantage, Baldinar approached Ashtaroth, the guardian in the Fortress of Ascension, and stole his being.
In a flashback, it showed how Baldinar got his hands on the Klara Libri from Kassias Grandiel and offered to help him on his research not knowing what the book truly contains.