Kingdom Hearts: OCS, Harem, teams, factions, and Death Battle

Lord Thanatos Bio:

Name: Lord Thanatos

Age: Millions of years old

Eye colour: red

Gender: male

Race: unknown

Biography: A dark, evil, powerful being that wields unimaginable power far greater than any force in existence throughout the entire Universe. 

He serves his master: The Dark Lord of the Shadows as his ultimate enforcer, seeing to his agenda, and spreading his evil across the worlds and beyond. Although his origins are currently unknown, it is said that Lord Thanatos shares many similarities with his master.

Lord Thanatos' body had a muscular, well-built physique, which looked partially robotic in appearance, standing 7'5" feet tall in height. His head was shaped like a black robotic skull, and he has luminous, demonic, glowing red eyes. He wore a triangular mask that covered his entire mouth. He wore heavily spike-studded jet-black armor with red pulsing accents, demonic skull-shaped pauldrons, full-length black clawed gauntlets, and black talon grieves. Embedded on his chest was a red triangular-shaped crystal that radiated with pure dark evil energy. He had ancient red runic markings all over his body. Underneath all his armor, he wore a black organic-looking bodysuit that appeared to be made of black muscle tissue from the neck down. He also wore two dark black belts on his waist and a long, ragged combat skirt. The cloth was a jet-black color and was ripped all around. The dark bodysuit had evil red glyph markings decorated all over it.

What lies in his soul is Pure Evil, Destruction, Domination, Ultimate Power, and Fear.

His Keyblade is The Harbinger of Shadows, the most powerful Keyblade of Darkness. Lord Thanatos' Keyblade was predominantly black and red. The blade was long, slim and extravagant with traces of black flesh on it. The teeth are diamond-shaped spikes that are connected by a black web structure. The shaft of the blade is a skull-shaped face in the middle with a menacing red eye of darkness with a black slit pupil situated just above the hilt. The Keyblade had a spiky, black guard with two crystalline demonic wings on its sides. The hilt was smooth and black. On the bottom of the black hilt of the Keyblade was a red oval glowing crystal gem. Its chain was very square and scary looking with four spikes on each side on each chain. The Keychain was shaped like a dark black flaming red eye with a black slit pupil. The Dark Keyblade also had evil twisted glowing red markings all over its teeth and blade. Both he and The Dark Lord wield this Dark Keyblade (Modeled after the Cursed Sword: Soul Edge from the Soul Calibur Series).

Much like his master, Lord Thanatos has many powers and abilities at his disposal that are said to be equal to any being in the universe in every way. As the Dark Lord's right-hand, Lord Thanatos can summon the Undead, Heartless, Nobodies, and the Unversed as well as the Forces of Darkness.

He can move at lightning speeds. Jump high long distances. Lift objects a billion times his size. Manipulate objects through willpower. He can instantly adapt to the environment to take maximum advantage of any condition or situation. Control devastating bolts of lightning that can leap between multiple targets. 

Become completely invisible in any environment. He can freeze a creature in near-permanent stasis through eye contact or by force of will. Even change the weather and manifest powerful, dangerous thunderstorms, tornadoes, blizzards, even hurricanes at will. He can consume all light in a large area and has complete control over darkness itself. 

In addition, he can unleash the darkness sealed in hearts and use it against others or to further the Dark Lord's agenda. He can drain the life force of any living being and absorb it into his body. Create and control multiple realistic illusions. Bind others to his will with total control using mind control. Invade the minds of other beings and read their thoughts. 

Drive others into complete insanity and fear. Can take control and possess the body of any living being. He is impervious to sub-zero temperatures and withstand intense heat. And has incredible resistance to pain and injury making him nearly invincible and invulnerable to any attack.

Lord Thanatos' power is so great like his master, he constantly radiates with pure darkness that constantly envelopes his entire body and dark lightning which constantly dance and crackle around his being. 

Even the souls of his enemies have fused with his heart adding a more demonic tone in his voice which is what makes him so fearful. Being an extremely powerful Keyblade Master of Darkness, he can even take on Devon and his friends all at once. This Dark Evil Being is a force to be reckoned with.

Lord Thanatos will stop at nothing until the Universe bows before the Dark Lord's infinite power and until he sees the Legendary Keyblade Wielder, Devon, dead at his feet. Lord Thanatos is the main supreme antagonist of the Kingdom Hearts Series along with other stories alongside The Dark Lord of the Shadows.

For voice reference, Lord Thanatos is voiced by Doug Bradley, the voice of Pinhead from the Hellraiser Franchise.