Freebooters in the Star Lanes
The terrifying and mysterious Khluulu are massive, tentacled horrors with an unspeakably ancient, alien culture. They travel in huge ships that look like asymmetrical, bloated snowflakes constructed of unknown metals. They enclose themselves completely in large fluid-filled tanks, and have rarely been seen directly by mortal beings. Their motives are inscrutable, and seem to put immense resources toward missions that no one else can understand. When they are encountered in open space, it is an even guess whether they will aid, attack, or ignore those who find them.
Khluulu interact with other races only via intermediaries called Ogwai, which they create by modifying captured (or purchased) members of other races.