Doctor Istan Zaly served as a scientist and researcher for the Separatist faction. Adjutant General Wilhuff Tarkin noted Zaly's significant achievements in dissecting the internal composition of kyber crystals, expanding on the initial research conducted by the scientist Marsabi. Zaly also developed his own theory, postulating the possibility of storing immense energy from kyber crystals within a defined physical area. Galen Erso challenged this concept during a conversation with Tarkin, dismissing it as "flawed" and cautioning against the impracticality of containing such a substantial amount of power. While working for the Separatists, Zaly invented a device known as the Zaly Shield. Doctor Chelli Lona Aphra stated that Zaly's hypothesis suggested that Kyber crystals formed in opposition to the Kyberite in which they were located, implying that Kyberite could be used to guide and channel the Force. This idea led the Separatists to believe they could enhance an individual's limited Force abilities, which prompted them to use the shield for this purpose. However, the Jedi who fought against those using the shield were able to turn the shield's own power against it. This, along with its considerable weight, rendered it largely ineffective in combat. As a result, the shield was eventually placed in secure storage within Dr. Zaly's secret base on Ringo Vinda, under heavy guard. At some later time, the Galactic Empire enlisted Zaly to contribute to the design of the Death Star's weapon, but he subsequently vanished.