Berserker pendant

Berserker pendants were talismans created by Berserkers which gave the bearer the ability to order people to do as they wished.

Properties
Each time it was used, the pendant slightly changed the bearer both physically and mentally until the bearer desired to complete the transformation into a Berserker. During transformation, the user would develop prominent blue veins over the skin's surface, and their irises would turn icy blue. The final form had the appearance of a man wearing animal skins. The only cure, if done early enough, was to remind the affected person who they were so that the memories would reassert their identity.

The pendant had the ability to give the user control over others, controlling the body, their will and altering emotions. However, the pendant didn't always give the user the ability to take away free will. It was also able to to control the electrical in the brain, as shown by Jacob West as he ordered Steve Wallace, Mr Cunningham and his classmates to be quiet; it caused their brains to stop sending signals to the vocal chords, causing them to lose their ability to speak as well as stopping them from moving, even when they wanted to. As shown by Paul Langer, it was also able of suppressing someone's memories.

There were three known ways the pendant could take back every order of those who used it. When Rani Chandra used it on Haresh Chandra, she then told him to forget everything she told him, turning him back to normal state of mind. As Jacob began tranforming into a Berserker, he resisted and begged the pendant to take back every order he gave when he was using it. After Paul Langer was freed from the pendant's influence, everyone that he had used it on had were returned to normal. (TV: The Mark of the Berserker)

History
According to UNIT archives, a Berserker pendant surfaced in a barracks in Ealing in 1940, but was lost during a German bombing raid. This same pendant was rediscovered by Jacob West, who used it for a time until it began to transform him, at which point he abandoned it.

Rani Chandra took it and used it for a while until she realised its dangerous properties when her father offered to die in response to an idle comment made by her, so she placed it in Sarah Jane Smith's attic. It was discovered by Paul Langer, who stole it and used it to control his son, Clyde.

Mr Langer was almost completely possessed by the power of the pendant until his wife and son reminded him who he really was. Clyde used the pendant to erase his mother's memories of the incident, then disposed of it in the sea. (TV: The Mark of the Berserker)