Sheidheda

Sheidheda (Dark Commander in Trigedasleng) is a minor character in the sixth season. He is portrayed by cast member Dakota Daulby. He is first mentioned in "The Children of Gabriel", and then debuts in "Memento Mori".

He was a Commander, given the title Sheidheda because of his dark history. He killed his own Flamekeeper and has been using the Flame to convince new Commanders to turn evil and kill people, including their own teachers. To help newly-chosen Commanders from being controlled by Sheidheda, the Flamekeepers came up with the Separation Ritual, during which the Commander calls upon the past Commanders to help stop Sheidheda.

Early Life
Sheidheda was born as a Nightblood and eventually became the Commander of the Grounders. Instead of following the teachings of his Flamekeeper, he felt like the Flamekeeper was trying to control him. He eventually became impatient and killed his own Flamekeeper.

Throughout the Series
In The Children of Gabriel, Madi mentions to Gaia that while listening to the past commanders, she has been hearing a commander who scares her. Gaia reveals that it is Sheidheda - the Dark Commander and asks Madi to avoid him.
 * -|Season Six=

In Memento Mori, Madi is communing with the other commanders including Sheidheda. Gaia mentions to Josephine (pretending to be Clarke) that Sheidheda is getting too strong and they need to perform the Separation Ritual to stop him. Josie ignores Gaia's advice and wakes Madi up abruptly. After that, the Dark Commander starts revealing himself to Madi whenever she looks in the mirrors. After realizing what's going on, Gaia tells Madi that they must perform the Separation Ritual right away in order to call upon the other commanders to stop Sheidheda.

During the ritual, Madi finds herself in a room with no one but the Sheidheda. Sheidheda tells Madi that Gaia is lying to her in order to restrict her. He tells her that his own teacher used to control him too; so, he killed him. He urges Madi to kill Gaia. Madi refuses and wakes up. Later on, after learning that Clarke is dead, Sheidheda convinces Madi that Gaia is to blame for Clarke's death. He asks Madi to kill Gaia but Madi banishes her instead. Taking advantage of Madi's anger and grieve, Sheidheda asks her to kill everyone.

Personality
He can be imagined as a demon, prompting Nightbloods to kill other people.

Physical Appearance
He wears a hood on him and he has white skin. He might have scars on his face.

Killed Victims

 * His Teacher

Notes and Trivia

 * He was a nightblood.
 * He was called the "Dark Commander".
 * His teacher chained him to a wall, which made him kill his teacher.
 * He might have been a feared ruler of Polis during his lifetime. This might explain why he wants Madi to kill others.
 * He is the first male commander shown in the series.