Lord met Thanatos while investigating to stop an illegal gambling operation in Girgas. Thanatos is a Black Dragon, an acquaintance of Celestial who treated him as a younger brother. According to Celestial, Thanatos fell asleep before the Great Flood occured and just recently woke up from his deep slumber. After that, he appeared to have spent the majority of his waking time fighting in an Arena, which is somehow connected to Lord's current investigation. Upon learning this piece of information, Lord immediately agreed to let Thanatos join his army per Celestial's request, also to keep him in check and potentially help further his investigation project. Unfortunately, Thanatos proved to be unhelpful regarding the information on the Arena since he could not care less.
Thanatos was given as the first log in reward into Fantasy War Tactics R.
* Stats reflected are base stats per star level without equipments, potentials, or skill bonuses