Hailing from the planet of Derris Kharlan, he traveled to Aselia in order to retrieve a Mana Seed that could save his homeworld from mana depletion. However, in order to do this he needed to charge up a large amount of energy inside of Yggdrasill and that's where things started to go wrong. The people of Aselia were going through an industrious age in which they were trying to harness large amounts of mana for machinery or magitech. This was draining away mana faster than Yggdrasill was producing it, not leaving nearly enough for Dhaos' Mana Seed.

Because of this, Dhaos set out to kill everyone who used or studied magitech by summoning an army of monsters. With their power at his command, he soon became feared throughout the land, eventually being challenged by the city of Midgards who sent five soldiers (the game's main characters) to storm his castle. He battled them and probably would have won had he not fled to the future for the sake his people.

Once there, Dhaos began terrorizing the planet again but was stopped once more, this time by a group of heroes led by Alan Albane. Using powerful magic, they sealed him away inside an underground tomb.

However, the sorcerer still wasn't ready to give up on his homeworld and so he used telepathy to contact a power-hungry knight known as Mars Udole. Dhaos promised him great power in return for his own freedom and the knight believed him, unlocking the tomb with two magical pendants... Only to be killed by Dhaos upon his release.

The five soldiers who had defeated him for the Midgalds had tracked him to the future using time travel and so Dhaos was forced to flee into the future once more. However, upon his arrival, he discovered that the entire world had adopted the science of magitech and so he felt he had no choice but to kill everyone...

Unfortunately for him, the soldiers from Midgards had followed him once more but this time they were wielding the Eternal Sword, an extremely powerful blade that could prevent the use of time travel. With nowhere left to run, Dhaos fought with all his might, drawing strength from his homeworld and even transforming his body to try and ensure his peoples' safety. Unfortunately, all of this was to no avail and Dhaos was ultimately killed at the hands of Cress Albane and his Eternal Sword...

However, during the final fight Dhaos had revealed his motives and the soldiers semmed to deem them just. Because of this, they asked the Goddess Martel to do them a favour and make Dhaos a Mana Seed to send up to Derris Kharlan along with his deceased body...