Hassat-durr was a set of Force abilities utilized by the Baran Do sages. When translated from the native Kel Dor language into Galactic Basic Standard, the term meant "lightning rod." The hassat-durr skills imbued the user's physical form with electromagnetic energy. Consequently, if a practitioner whose skills were not fully developed attempted to employ these techniques during a thunderstorm, they would be repeatedly struck by lightning. However, once mastered, these abilities enabled the user to disable prosthetics and electrical implants, disrupt shock shackles, function as a range-extending antenna for a comlink, and even generate a non-Dark Side version of white colored Force Lightning for various purposes, including utility and combat.
The ayna-seff technique—which translates as "dead brain"—belonged to the hassat-durr family of abilities. It took Jedi Knight Jacen Solo a total of three days to achieve mastery of this technique, whereas Grand Master Luke Skywalker accomplished the same feat in only two days. Master of the Order Koro Ziil imparted this skill to Solo in 34 ABY—before Solo's fall to the dark side and transformation into Darth Caedus. However, by the time Skywalker arrived on Dorin, Ziil had ascended to the position of leader of the Hidden Ones, a clandestine sect within the Baran Do. Tila Mong then succeeded her as Mistress of the Order, and she instructed Skywalker in this ability. Luke Skywalker later utilized this power to regulate unstable electrical surges within the Jade's Shadow, thereby preventing damage to the vessel.