Nightmare

"The time is ripe, you shall become part of me. You are my first sacrifice" -Nightmare, Soul Calibur III

Nightmare is a character in the Soul Calibur franchise and the series main antagonist.

Characteristics
Nightmare is the living embodiment of Soul Edge, an evil sword that grows in power everytime it is bathed in the blood of combatants. Nightmare has appeared in every Soul Calibur game, although in different forms for most of them. In each game Nightmare's appearance has become more and more demonic, such as his appearance in Soul Calibur V, his right arm has been completely covered in flesh and bone while his hand has developed into more of a large claw.

Nightmare is not a person himself, but a host for Soul Edge. He is just a body for which the Evil sword can use to gain more power, Nightmare is just a tool or weapon to serve Soul Edge. Nightmare looks down on Humans and sees them as pathetic creatures that he can slaughter without mercy to gain more power for Soul Edge. Sometimes Nightmare even considers killing and absorbing some of Soul Edge's most loyal servants such as Tira.