|Tharn, a male Halkan|
In 2267, he informed the landing party from the ISS Enterprise that his people would not allow the Terran Empire to mine dilithium on their planet because they knew the Empire would use this resource to make war on other worlds. The ISS Enterprise was under orders from Starfleet to annihilate the Halkans immediately if they didn't grant these rights, but James T. Kirk, who had replaced his mirror counterpart due to a transporter accident, stalled for time and said the Halkans had twelve hours to reconsider. Tharn said twelve thousand years would make no difference; his people were prepared to die as a race if that was what it took to protest the Empire's policies. He also warned that one day all the Empire's subject worlds would revolt (TOS: "Mirror, Mirror").
Tharn was killed when the mirror universe Kirk was returned to his universe and ordered the Halkan race be annihilated (TOS novel: The Sorrows of Empire}.
Mirror universe trilogyEdit
Spock and Kirk convinced Starfleet that the Halkans were secretly allied with the Klingons, so that if the Empire moved against that one planet the Klingons would have an excuse to declare war. Kirk received honors for avoiding such a devious trap. Tharn's fate is unknown, but the Halkan homeworld didn't fare well once the Klingon-Cardassian Alliance took over (Shatnerverse).
In The Final Days Spock obtained dilithium concessions from the Halkans in exchange for a promise to follow through on the other Kirk's urging, convincing them that they could be of more use as a role model for his reforms than as an extinct race. Tharn became Halka's representative in Spock's government, and died from natural causes before Spock was overthrown. Ironically Spock's government fell because of the influence the Halkans had (The Final Days, A Debt of Honor).