Algol

Algol (アルゴル Arugoru) is a character in the Soul series of fighting games and the main antagonist in Soulcalibur IV. He can be played like other standard characters, but must be unlocked by defeating him in Story Mode. He appears as one of the final bosses along with Siegfried and Nightmare. Algol has also returned for the portable version of Soulcalibur IV: Soulcalibur: Broken Destiny, along with the next main series game: Soulcalibur V.

Biography
Algol, also known as "The Hero King," was able to obtain Soul Edge and, with an indomitable will, avoided being controlled by it. According to the legend, he used the sword to spread peace among the lands. His son, Arcturus, jealous of his father's power, took Soul Edge, unaware of its malevolent properties, and was possessed. Algol battled and defeated his son with a fatal strike.

Remorseful after his son's death, Algol desired to create a sword to counter the evil within Soul Edge. The legend says that, using purified shards obtained from the battle with his son and the assistance of various sages, Algol was able to create Soul Calibur after many failed attempts and the sacrifice of his own life. However, the "successful" ritual produced unexpected results: the blade created was extremely similar in nature to Soul Edge due to the restlessness in Algol's soul. The tribe that was tasked with the protection of the new sword slowly purified it, sealing the Hero King's soul, keeping his thirst for power dormant over the centuries.

During the immense surge of power released when the cursed sword and the spirit sword clashed, Algol's soul, then formless, was able to absorb a small fraction of the energy. With what little he gained, he built himself a body fashioned after his older one, as well as a tower, which he deemed the "Tower of Remembrance", to reside in. Algol knew that it all would not last—once the power he absorbed had been used up, everything he had created would disappear like a mirage. He needed to obtain the swords if he intended to remain a reality. The Tower of Remembrance's sudden appearance would draw warriors to him. The swords, he knew, must be amongst them. Forging himself weapons based on memories of the cursed sword and the spirit sword, he waited patiently for the first arrivals.

Soul Calibur V
Always a man in search of a conquest, Algol now has placed his eyes on taking over the real world by corrupting it with the energy of the Astral Chaos. In trying to do so, he's attempting to control the energies of the realm, which forms his ethereal body. Edge Master is the only one who notices this "corruption" going on, and has entered the Chaos to fight the Hero King. However, he's not sure he can keep up with him, even if going all-out.