- "There is no war within the walls. Here we are safe. Here we are free."
- ―A Dai Li agent
Brainwashing was an illusionary technique developed by Long Feng that incapacitated any of those who opposed his rule. Utilizing the Dai Li to enforce his will during the Conspiracy of Ba Sing Se as a means to keep Ba Sing Se's citizens from speaking about the Third Great Shinobi War, this allowed the Dai Li to alter attitudes, beliefs and mold personalities as they pleased.