Hass'terral was a planet located in the Badlands and was a Cardassian Union military research base which belonged to the Obsidian Order.
By the mid-24th century, the base was a heavily defended location which contained gravitic mines, disruptor fields and a battalion of soldiers to protect it from intruders.
In 2373, in order to capture the Red Orbs of Jalbador that were in Leej Terrell's possession, Major Kira Nerys disguised herself as a recently recruited Cardassian scientist called Alira Rejal. Once she infiltrated the facility, she managed to sneak Captain Benjamin Sisko and Worf into the base where the three of them managed to confront Terrell. However, just as they reached her, Obanak Keelen transported inside with a squad of Grigari and took possession of the Red Orb whereupon he left Hass'terral. (DS9 video game: The Fallen)