The Druids' origins are unknown in the series, neither how they came to join the Empire, other than the fact that they are led by Haggar and assist her with their various Quintessence experiments to further increase the power of Galra Empire. Among their innovations was the Komar, which they used to extract all the quintessence from planets, which would have taken years using standard mining operations. Aside from quintessence experiments, some of them patrol the Galra Command Ship and refine quintessence containers into Galra fuel.
Following Lotor's rise and fall of power, the Druids are ordered to combat allied forces of Voltron Coalition and Blade of Marmora. By the events of "The Ruins", the Druids suffered an enormous losses aside from Macidus, the last known survivor, had managed to destroy majorities of Blades where some of them were lured with Kolivan's signal. With Macidus' death, the Druids are truly gone from the universe.
All of the Druids wear long brown robes that conceal much of their bodies, usually exposing only their hands. Aside from Haggar, all known Druids appear to wear white masks on their faces that make it appear as though they have more than two eyes.
Through Macidus, the druids revealed to hail from a humanoid alien race which characterized with human-like features much like Alteans, but with grey skin, lack of visible nose, and yellow eyes with no visible pupils. They also have five fingers on each digit and 3 toes on each legs. Though their nature as sapient beings has been foreshadowed through their ability to communicate verbally with Haggar and Thace as well as other activities they performed by their own will, it's yet to confirmed whether they are Galrans.
Little is known of the Druids outside of their presence on Zarkon's Command Ship and loyalty to Haggar. Elsewhere in the Empire, Druids have been seen using their magical abilities to refine Quintessence into Galra standards for fueling the Empire's needs.
Draped in flowing, black robes that only expose their hands and donning pointed masks to hide their faces, the Druids operate as guards on the Command Ship and are the ears and eyes of Haggar. They investigate suspicions of spies and brutally interrogate captured prisoners. They assist the witch in utilizing the Komar device and infusing their lord, Zarkon, with Quintessence, as well as enhancing his ability to track the Black Lion and take control of it. Their magic not only allows the manipulation and refinement of Quintessence, but also to study information from Galra Sentries and fire devastating blasts of dark magic at opponents.
In battle, all Druids possess magical abilities similar to Haggar albeit less powerful scale, which include energy manipulation, enhanced mobility, and teleportation. They are capable of refining raw Quintessence into fuel for the Galra Empire. Druids are also effective as interrogators and in experimentation with robotic elements to enhance soldiers and create Robeasts.
Zarkon also makes use of the Druids' magic to enhance the link he has with the Black Lion, being its former Paladin, allowing him to track Team Voltron anywhere, and take control of it at close range. Since Shiro has deepened his bond with the Black Lion, it has weakened his connection.
The Druids are capable of hovering and teleportation to outmaneuver their enemies, disappearing and reappearing in an instant. When mortally wounded, they disappear in a blast of bright energy. Suggestively, while possessing large amount of magic power within their very being, a Druid's body is barely able to contain the power despite their mastery over it; physical injuries can disrupt the flow of magic within them that if the inflicted wound is severe enough, it would trigger a chain reaction that woul corrode them from inside-out.
- The white, bird-like masks worn by Galra druids bear a passing resemblance to those worn by plague doctors in 17th century Europe.
- In the episode Collection and Extraction, the Druid seen refining Quintessence makes an odd, screech-like cry when Keith attacks, and lets out a similar cry as it fights him.
- Two of the six Druids stationed at Zarkon's Command Ship are killed by Keith and Thace. A third is killed by Kolivan. Dozens more would eventually killed by the events of Season 7.