The Kkore were a race of giants from an area outside the galaxy called known as "Grey Space".
Figures of myth and legend, tales dismissed as apocryphal most galactic denizens described a conquest aeons of cycles before the present, with an ominous warning of their return, which, as said, happened after a millennia of planning, they struck at an opportune time as the galaxy was still reeling from the devastation wrought by the recent conflict between the Peacekeepers and the Scarrans.
They invaded the Milky Way Galaxy with hopes to conquer it after over a thousand cycles of planning. Delvians evolved from this race, and the Kkore were ultimately defeated by a rag-tag armada of species from around the Uncharted Territories due to help from the Delvians. ("The Beginning of The End of The Beginning")
Unlike their Delvian descendants, who were of average Sebaceanoid height and build, the Kkore were at least twice as tall as the standard Sebacean.
The Kkore was a warrior culture despite their technological sophistication, believing conquest to be its own reward.
Kkore technology was far more sophisticated than most, if not all, of the civilizations of the known galaxy it outpaced the Peacekeepers by several hundred cycles