Sheng

Dr. Sheng was a scientist stationed in Earth Empire's southern forces during the rule of Kuvira, and continued to serve in an armed holdout outside Gaoling in the months following the latter's surrender. Sheng was influential in the development of highly effective brainwashing techniques in the hope of influencing the Gaoling Election of 174 AG.

Early career
Dr. Sheng worked very closely with Baatar Jr. before he left to become Kuvira's second-in-command. Afterward, Sheng began researching more effective methods to reeducate prisoners sent to camps. She researched the ancient indoctrination techniques used by the Dai Li. However, noting that the Dai Li's methods could be unreliable, Sheng combined the the methods with modern technology and began experimenting with magnetic waves to alter the brain. She considered this form of brainwashing to be permanent.

Kuvira surrendered before Sheng was able to share her discoveries, although Kuvira later indicated she would have shut down Sheng's inhumane experiments.

Influencing the Gaoling election
Shortly after announcing his candidacy to run for governor of Gaoling, Guan lamented to Dr. Sheng how disappointed he was at how Kuvira was no longer the commanding woman who inspired them, and stated his belief that Korra's influence had corrupted her mind. When Dr. Sheng suggested recalibrating her mind, Guan did not rule it out, but chose to focus on winning the election. He asked whether the first campaign recruits had arrived, prompting the doctor to bring him to a tent. All of the "recruits" were being brainwashed, repeating Guan's campaign slogan. Avatar Korra, Toph Beifong and Earth King Wu later found that much of Gaoling had fallen victim to Sheng's brainwashing.

After Kuvira, Asami Sato, Mako, and Bolin were captured and brought to Sheng, she prepared to begin brainwashing them. When confronted by Kuvira on the supposed inhumanity of her experiments, she told her that she was naïve and never cared how her followers achieved the results that she wanted. Sheng proceeded to successfully brainwash Asami, Mako, and Bolin, and prepared to do the same to Kuvira before she escaped from the camp.

Dr. Sheng later prepared to brainwash Earth King Wu after he was successfully captured by Guan's forces.