Fifth Brother's Species

The Fifth Brother's species is an unnamed Force-sensitive humanoid race. A male member of this species, the Fifth Brother, was a Jedi that fell to the dark side and joined the Galactic Empire as an Inquisitor.

Biology
Members of this species are externally very similar to Humans, but bear mint-colored eyes and grey skin, along with some distinctive line-like dark markings on their faces, which appear to bound their eyes and mouths. They are Force-sensitive, capable of becoming Jedi or harnessing the dark side.

History
At some point before 19 BBY, a male member of this species was taken into the Jedi Order as a youngling. In 19 BBY, Jedi-turned-Sith Anakin Skywalker and all clone troopers of the Galactic Republic turned on and massacred the Jedi under Order 66, a command from Chancellor Palpatine, who was in truth the Sith Lord Darth Sidious. This individual survived the order, and was soon taken by the newly formed Galactic Empire, drafted into the Inquisitorius alongside other Force-sensitives, made into a Jedi-hunting assassin and given the name of Fifth Brother. While first trained under the Pau'an Grand Inquisitor, Anakin, now a cyborg known as Darth Vader, was soon placed in charge of the Inquisitorius, and began an even harsher form of training, which resulted in the Fifth Brother getting his right hand cut off during a training session with Vader.

After replacing his lost hand with a cybernetic, the Fifth Brother was later sent on a mission to hunt down the Jedi Eeth Koth, who had also escaped Order 66, although the Fifth Brother noticed strange behavior from two of the other Inquisitors, who appeared too intimate with each other. He reported their actions to Vader, who later found that the two were traitors, leading to him personally killing them while ordering the Fifth Brother and the other Inquisitors to stand down.

In 9 BBY, the Fifth Brother continued to hunt Jedi to the Outer Rim, coming into conflict with the Third Sister, a Human Inquisitor who he found to be too defiant and obsessive, especially with the prospect of capturing Obi-Wan Kenobi, Anakin's former master who had escaped Order 66. The Fifth Brother stayed loyal to the Grand Inquisitor throughout the hunt for Kenobi, rebuking the Third Sister every time she stepped out of line, as he outranked her.

By 4 BBY, the Fifth Brother was assigned to deal with the growing Rebellion, first targeting a group of Lothal-based rebels, joining with the Seventh Sister, another Inquisitor assigned to the same task. While they confronted and fought the rebels several times, including two Jedi among them, Kanan Jarrus and Ezra Bridger, they failed to eliminate the Lothal cell, or the rest of the Rebellion. In 3 BBY, the Fifth Brother was ordered to retrieve a Sith holocron from Malachor, along with the Seventh Sister and Eighth Brother. There, they were met with Jarrus and another Jedi, Ahsoka Tano, who were soon joined by Ezra and former Sith Maul. Engaging them, the Seventh Sister was soon killed by Maul, and the Fifth Brother then had his lightsaber disabled by Tano, before being killed by a slash from Maul.

Appearances

 * Star Wars Rebels s02e04, "Relics of the Old Republic" (2015)
 * Star Wars Rebels s02e05, "Always Two There Are" (2015)
 * Star Wars Rebels s02e10, "The Future of the Force" (2015)
 * Star Wars Rebels s02e11, "Legacy" (2015)
 * Star Wars Rebels s02e18, "Shroud of Darkness" (2016)
 * Star Wars Rebels s02e21-22 "Twilight of the Apprentice" (2016)
 * Obi-Wan Kenobi (2022)