Whether the Japanese were worse than the Nazis is hard to say. Probably not - although Prisoners of War may well have been better treated by the Germans
But what they did was certainly bad enough.
There's the Rape of Nanking
Tribo ’BBC NEWS | World | Asia-Pacific | Scarred by history: The Rape of Nanjing
There's biological warfare experiments (Unit 731)
http://www.arts.cuhk.edu.hk/NanjingMassacre/NMU731.html
There's the use of "comfort women".
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