We meet after a thousand years, now thou shalt taste the power of the Stahlritter!
- —Duvalie's intro quote, Trails of Cold Steel III
You’ll learn soon enough just how different you and I are as knights!
Duvalie (デュバリィ Dyubarī) is the head knight of Ouroboros’ Stahlritter (鉄機隊 Tekkitai), a battalion under the direct control of Arianrhod.
A young girl with brown hair tied in a bun, with emerald eyes. She wears a light-bronze suit of armor plated boots up to knee pads, waist guards, chest-plate to shoulder, elbow to hand gauntlets, while underneath is a grey-violet suit for the armor. A decorative broth on the front of the plated chest around the neck area that has two light-blue jewels. Another additional feature is a magenta-violet color drop cloth on the front between her legs and in back connected to the armor waist armor plate, giving style of a female knight. She wears a light-bronze headband with a jewel front center, two wings on both edge sides by the ear. When on the battlefield, she wields a shield with the same style as her knightly armor and center jewel in the middle for the left hand, and wields a sword slightly longer sword customized pattern of force. All in all, she takes on the appearance of some female knight who may look like a teenage girl dressing up, but maybe…that’s the off way to lower one’s guard.
Unlike all knights who are bound to the code of chivalry, Duvalie is described as a "tsundere" who hot-tempered, ever-willing, devoted, short-tempered and bragging. But her character portrays her suit for battle than living the life of a delicate woman, boasting that she’s a swordsman who cannot be bested. However deep down, she is sincere who refuses anything that strays from the righteousness.
Her loyalty Arianrhod is fierce to the range from devotion to adoration wher she becomes a complete fanatic. The admiration of her leader leads her to brag about her invincibility, and will not let anyone say otherwise. But can become overly emotional rather quickly, which can result in her slipping up and making costly mistakes.
Under the guidance of the Steel Maiden, Arianrhod, Duvalie has become a strong swordsman whose speed and swiftness have become on par with Leonhardt the Bladelord after the latter's demise. With her built-up speed, Duvalie's swordsmanship makes her unmatched probably against a squad, thus earning her alias, Duvalie the Swift (神速のデュバリィ) and made head knight of the Stahlritter.
Duvalie works within apart of Ouroboros albeit the Grandmaster's will, where her only is only for her master. While only the Grandmaster selects which member is selected "leader" of the ranks, Duvalie's skill was actually enough to be one, but that person needs to be burdened by some darkness; which to Rean’s point of view, Duvalie doesn’t strike as someone that carries any kind of darkness. However even without being an Enforcer, so long as her lord wills it, Duvalie will fight ill she’s breathed her last.
Battle Scope: Head knight of the Steel Maiden-led Stahlritter. Her swordsmanship is too swift for the naked eye.
- Flame Brand: Wields up her blade to become covered in fire underneath of a red-orange spell circle. Then after getting into a position, swings it around to hit her targets causing a great deal of damage.
- Ice Brand: Wields up her blade to become covered in ice underneath of a light-blue spell circle. Then after getting into a position, swings it around to hit her targets causing a great deal of damage. Effect: CRITICAL.
- Lightning Brand: Wields up her blade to become covered in lightning underneath of a yellow spell circle. Then after getting into a position, swings it around to hit her targets causing a great deal of damage.
- Shadow Brand: Rears her blade back while a form of wind covers below her, before dashing off in a dark violet in striking her enemy in a fast motion with a big step of damage before reappearing where she was.
- Illusory Brand: Wields her blade up while a glow of energy comes around her. Then appearing from dark light-violet mist are two more copies of her in forming a trap triangle formation on a target. Then all three lash off to attack with quick sword swings as a flash of bright flaring light, dealing a great amount of damage before the two illusions fad.
- Prism Calibur: Duvalie wields up her blade to swing it downwards, which she then splits off into two image forms of herself on both left and right side while getting into posotion. Then they dash across the field, striking their targets in a first row of attack pattern, then a second attack patterns, and just continues doing so in making a bright violet light mark trail. Afterwards, she’ll appear on one side to charge up her sword with a brightly blue and violet light, before diving off to take a big swing of unleashing a wave circle form to impact all of her targets in delivering a massive among of damage to almost finish them off.
- In the english dub, she speaks the knightly vocabulary in the Medieval ages when in armor.
- For reasons unknown, she harbors a personal resentment towards the Arseid family, despite the family's tradition stems from the original Maiden and her knights.
- Her sword and shield fighting style seems similar to the Soul series character Cassandra Alexandra, a knightly type female.