Cancri (species)

From Tardis Wiki, the free Doctor Who reference

The Cancri were a gaseous species at war with the Ba-El Cratt.

They came from Cancri. They offered their technology to the Human Empire to take diamonds from Saturn, allowing the humans to also take a cut. They used these diamonds in weapons that used a form of Raman Amplification system to deploy against the Ba-El Cratt. (PROSE: Diamond Dogs)