Ziost's breeding pens, found on Ziost, were the areas in which Kissai Ninûshwodzakut developed and crossbred warbeasts for use by the Sith. After obtaining the Holocron of King Nakgru in 6899 BBY, Jen'jidai Sorzus Syn made a trip to these breeding pens and analyzed the process of creating warbeasts, including species like silooth, warbirds, war behemoths, hssiss, terentatek, battle hydras, chrysalides, war wyrms and guardian creatures referred to as tuk'ata. In her own chronicle, Syn commented on how much of a "delight" it was to arrive among the other alchemists.
The resource guide Book of Sith: Secrets from the Dark Side, authored by Daniel Wallace, contained the initial reference to Ziost's breeding pens.