Cyberlord

The Cyberlords were a later stage of Cybermen who had become peaceful. They were either descended from the Cybermen or based their technology on them.

They were organised as the Cyberlord Hegemony, which existed as one of the major political powers during the time of the Union. (PROSE: The Crystal Bucephalus) The Hegemony was ruled by an Emperor Brandt and utilised the ArcHive, a supercomputer created in the 100th century. (PROSE: The Quantum Archangel)

They had been peaceful for several centuries before the 101st century, after the Cybermen had nearly died out. (PROSE: Synthespians™)

The Time Lords of the Sixth Doctor's time knew of a future where the Cybermen would become peaceful, eventually evolving past physical bodies entirely. They oversaw a possible origin of the Cybermen on Marinus and did not heed the Doctor's wish to undo the events, as they believed this ultimate future evolution well worth the centuries of conflict and death. (COMIC: The World Shapers)

In an alternate timeline created by the Quantum Archangel, one that reflected the future War in Heaven, the Cyberlords were considered the Time Lords' greatest allies before their history was rewritten, turning them to the side of the Enemy. (PROSE: The Quantum Archangel)

Behind the scenes
While the Cyberlords' return to traditional Cybermen behavior in PROSE: The Quantum Archangel was in the context of an alternate timeline, Craig Hinton and Chris McKeon's Time's Champion strongly implied the once peaceful Cyberlords were now, once again, a scourge on the galaxy.