周瑜打黄盖
Zhōu Yú​dǎ Huáng Gài

connivance

周瑜打黄盖 (周瑜打黃蓋) Zhōu Yú​dǎ Huáng Gài
connivance
A figurative situation where both parties are willing participants in a ruse or a deceptive arrangement, even if one side appears to be mistreated.
stratagem
The historical or literary military ruse from the Battle of Red Cliffs where General Zhou Yu staged a beating of Huang Gai to deceive Cao Cao.

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CC-CEDICT