fight fire with fire
US /faɪt ˈfaɪər wɪð ˈfaɪər/
UK /faɪt ˈfaɪər wɪð ˈfaɪər/

1.
火には火で, 毒を以て毒を制す
to use the same methods as your opponent, even if they are unpleasant, in order to achieve a victory
:
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When they started spreading rumors, we decided to fight fire with fire and expose their lies.
彼らが噂を広め始めたとき、私たちは火には火で対抗し、彼らの嘘を暴くことにした。
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Some argue that to deal with cyberattacks, you sometimes have to fight fire with fire.
サイバー攻撃に対処するには、時には火には火で対抗しなければならないと主張する人もいる。