尔虞我诈 (爾虞我詐) ěr yú wǒ zhà

ěr yú wǒ zhà set phrase you hoodwink me and I cheat you; mutual deception/each tries to outwit the other
Domain: Idiom 成语
Notes: (CC-CEDICT '爾虞我詐'; Guoyu '爾虞我詐')