An extreme muscle pain disease called Sumisu no Koen infects its victims, beginning with unbearable agony, to which the infected will pass out with ease. The victim is later on completely brainwashed under his nose.
Dakukunshu created Sumisu no Koen solely to infect Riesdeath with it. It was, of course, successful.
Dakukunshu’s method in creating this disease is vague, for in spite of the in-depth explanations provided by governments dotted all around Ninjago, Dakukunshu’s majestic ability to hijack electronics prevents any true information evaluating Sumisu no Koen’s creation from being released or told genuinely. The most believable article states that Dakukunshu used a sweaty mixture of oni horn shavings, rattlesnake fang powder, literal fire, and a list of two hundred and thirty more dangerous, cell-destructive chemicals.