Nyder

Security Commander Nyder was a military officer in the Kaleds' Military Elite and the assistant of Davros.

Meeting Davros
Following a rescue operation of Davros from a Thal Dome, Davros promoted Nyder from Lieutenant to Security Commander prior to his take-over of the Kaled government. (AUDIO: Guilt) By another account, Nyder was already the Kaled Security Chief before Davros had cybernetically augmented himself. Alongside General Ravon, Nyder was horrified when he saw the first Dalek drone and was intimidated into giving Davros all the resources he wanted to make more. (PROSE: Davros Genesis)

The Creation of the Daleks
By the time that the first fully functional Daleks had been created, Nyder had become Davros's most trusted associate, and his personal aide. Icily efficient, he obeyed Davros' every order. After the Fourth Doctor and Harry Sullivan had escaped into the residential block of the Kaled Dome, Nyder's spies reported the meeting to him, information that Nyder brought to Davros. With his master, Nyder then travelled to the Thal Dome, bearing witness to Davros' betrayal of their race.

Returning to the Kaled Dome, Nyder duped Gharman into giving him the names of those who opposed the Dalek project before capturing the Doctor, Harry and Sarah Jane Smith. After the Doctor had been forced to reveal information about the Daleks' future defeats, Nyder took Sarah and Harry away, returning to save Davros from being threatened by the Doctor into giving an incontrovertible order that would have ended the Daleks.

The Doctor and his companions managed to escape and take Nyder hostage, forcing him to break into Davros' office for the Doctor's recording, but Nyder fled after the recording was destroyed.

After the Daleks had begun populating the Kaled bunker, they began rebelling against Davros, manufacturing more of themselves without his consent. When they refused to shut down the production line, Davros ordered Nyder to do so only for the Daleks to promptly exterminate him. (TV: Genesis of the Daleks)

Personality
Nyder was ruthless and utterly loyal to Davros, obeying orders without question. Despite certain misgivings about Davros' complex and indirect schemes, preferring a more conventional military approach, he never wavered and took no issue with the genocide of his own people and the Thals to achieve Davros' goals. (TV: Genesis of the Daleks) Over the years, he grew dependent on Davros' support, feeling abandoned and lost without it. As such, he effectively needed to be given orders from the insane genius in order to carry on his daily life. (PROSE: Doctor Who and the Genesis of the Daleks)

His dedication to Davros was so complete that he never doubted Davros, causing him to disbelieve the Fourth Doctor's claim to be an alien, because Davros had said Skaro was the only planet capable of supporting intelligent life. Cunning and sly, though not as intelligent as Davros, he still managed to deceive members of the Scientific Elite into revealing their treachery against Davros and helped in their destruction. (TV: Genesis of the Daleks)

Behind the scenes

 * Aside from his appearance in the audio story Guilt, Peter Miles returned in the role of Nyder for two one-off productions of the play The Trial of Davros. In the first production, he appeared alongside Michael Wisher, the original actor to play Davros; and in the second, following Wisher's death, appeared alongside Terry Molloy, who took over the role of Davros from Resurrection of the Daleks through Remembrance of the Daleks.
 * Peter Miles is credited as "Nyder, Kaled Security Commander" on the sleeve of the Genesis of the Daleks LP.
 * Miles based his performance as Nyder on . Miles later said he was always fascinated by the mentality of men corrupted by power who deceive themselves into believing they are acting for the greater good. (INFO: Guilt)