Saki Mitsurugi

Saki "Tsuru" Mitsurugi (美剣) is a mysterious girl and the secondary antagonist character who becomes the latest addition to the cast of Ultraman R/B.

Lacking a name of her own (hence being credited as Mysterious Woman (謎の女性) in episodes 11 and 13), she received her name from Asahi during their first encounter.

Pre-Ultraman R/B
Saki Mitsurugi comes from somewhere far away, being on Earth since ancient times and had met several notable historical figures during her travels around Earth in the past.

Ultraman R/B
Saki Mitsurugi first shows up after Ultraman Orb Dark defeats Horoboros, and she takes its R/B Crystal. She then appears when Orb Dark and Ultramen Rosso and Blu start to fight, and she summons Horoboros, which somehow evolves into its Bipedal form. After Horoboros defeated the Ultras, Saki called the Kaiju back in its R/B Crystal before summoning again later on to fight Rosso and Blu, who was able to defeat it with the Triple Origium Ray. Afterwards, Saki posed as a nurse and entered Aizen Tech and meeting an injured Makoto Aizen for the first time. Saki also shown her interest towards Asahi, leaving the R/B Crystals of Belial and Ultraman behind after meeting her personally and having a brief conversation with her before lending Makoto her Gyro, allowing him to transform into Grigio King and successfully taking his revenge against Rosso and Blu. Saki then declared herself as the new master of D.R.L.N. while overseeing the battle. Following Grigio King's defeat by Ultraman Ruebe, Saki separated Cereza from Makoto's body and trapped him within the building premises and took over Aizen Tech as its new president, replacing Makoto, who had returned back to normal.

Powers and Weapons

 * Longevity: Saki has lived a very long life, having met Tokugawa Ieyasu during the late sixteenth century, as well as figures such as Oscar Wilde , William Shakespeare and Niccolò Machiavelli.
 * Gyro: A repainted version of the original Gyro, it sports orange and black accents.
 * Kaiju Summoning/Transformation: In the same vein as Makoto Aizen, scanning R/B Crystals allow her to summon or transform into the corresponding Kaiju.
 * Empowerment: A unique feature of her Gyro, Saki can evolve monsters summoned from R/B Crystals into their stronger forms.
 * R/B Crystals: Although she is yet to have her own set, Saki can still use the R/B Crystals on her own Gyro.
 * Kaiju Return: Saki reverts a summoned monster back to its R/B Crystal, which flies back to her.
 * Teleportation: Saki is capable of disappearing within the blink of an eye, doing so to escape before Katsumi witnesses her presence.
 * Energy Pulse: Saki releases a pulse of energy from her hand, which was used to expel Cereza from Makoto Aizen's body.

Kaiju

 * Horoboros: Retrieved after the Kaiju's first defeat.
 * Grigio King: Unknown
 * Neronga: Unknown

Ultra

 * Ultraman (Given to Asahi Minato)
 * Ultraman Belial (Given to Asahi Minato)

Trivia

 * During her first photograph, Saki is shown with a blank R/B Crystal. Its true purpose is unknown at this point, but is likely to be the Horoboros Crystal.
 * In her intro card during the opening sequence, there are three grey blobs which seem to vaguely resemble the three Grigio variants.
 * The color of her fingernail paint represents the three Ultras:
 * Red: Rosso
 * Blue: Blu
 * Black: Orb Dark
 * For reasons unknown, she disguises herself when meeting different people, such as a nurse (towards Makoto) and a high school girl (towards Asahi).
 * Her given name is shared with an alien girl from Ultraman Tiga, who also wears black clothes and has been on Earth since the ancient times.