In the mirror universe, Sarek was Spock's father.

Dark Mirror continuity Edit

In the Dark Mirror continuity, Sarek was an ambassador. Spock had transferred off the Enterprise shortly after a transporter accident had brought visitors from the primary universe, and supported a program of reforms until his former Captain James T. Kirk framed him for treason and had him executed in 2279. Shortly after Spock's execution, Sarek himself was assassinated by another Vulcan seeking Sarek's position. (TNG novel Dark Mirror).

SpectreEdit

Sarek was the Arbiter of the Vulcan Mineral Syndicate, one of the most powerful business lords on Vulcan. Spock relates in Spectre that Sarek was assassinated in 2267 by Orion spies during the Empire's mission to annex Coridan, and that Kirk destroyed Coridan for its perceived role in the assassination. (TOS novel Spectre)