The Taklarians were a warlike Aryan race, having practised selective breeding for centuries; as a consequence, they were all nearly seven feet tall with deeply bronzed skin (and consequently were known colloquially as "Bronzers"), being particularly arrogant and certain of their superiority over others.
When the destruction of Sarath's moon threatened to destroy the planet, they attempted to invade the city of Arkhaven, which had begun construction of a ship that would take them to the neighbouring planet Mirath, but the Arkhavens refused to allow them on board due to space concerns and their moral repugnance at the Taklarians' history. The battle continued for some time, resulting in the destruction of much of the outer areas of the city and the deaths of several Arkhavians through the Taklarians' use of chemical warfare, but concluded with the apparent death of all Taklarians when their ships were destroyed.
However, a tenth of the flagship's crew survived the crash, with the Arkhavians leaving the ship alone as a symbol of their victory. While the small crew lacked the power to mount a direct assault on the city, they were able to draw out their remaining supplies while they dug underneath Arkhaven to infiltrate the city's sewers. They had intended to use mental conditioning to create a series of sleeper agents that would help them infiltrate the ship, but their only "agent" was Barbara Wright, who found them by chance after she was trapped in the sewers when a building collapse, and they never had the chance to plant more agents.
When Zero Day was declared ahead of schedule after the moon broke in half, the Taklarians attempted to take the Ship, exploiting the fact that the city was far less populated than they had anticipated to mount a surprise assault while the Watch were occupied with the evacuation to the Ship. Having taken the Ship, the Taklarians intended to demand various Arkhavian women for breeding purposes, keeping the Arkhavians alive to serve as their slaves until they died out due to their 'inferior genetic stock'. However, once Prince Keldo reached the ship's control cabin, he was confronted by Mayor Brantus Draad over a video communication, Draad revealing to Keldo that he had always intended to destroy the Ship- which was actually an elaborate deception to calm potential panic as the city really didn't have the means to create a working vessel of that size — with the Taklarians' presence just making it that bit easier for him to do what had to be done, triggering the explosives to destroy the Ship, killing the Taklarians and all the natives of Arkhaven he couldn't save. (PROSE: City at World's End)