Following are a number of back-translations as well as a sample translation for translators of Proverbs 21:22:

• Kupsabiny: “A wise person (can) fight a city of brave people,
  and destroy the wall that those people depend upon.” (Source: Kupsabiny Back Translation)
• Newari: “Wise people attack a city of strong people.
  and they tear down the strong fortress
  in which they trust.” (Source: Newari Back Translation)
• Hiligaynon: “A commander who is good in tactics can-capture a city with many soldiers, and can-destroy its stoned-walls which those soldiers rely-on/trust-on.” (Source: Hiligaynon Back Translation)
• Kankanaey: “A wise-person is-able-to defeat the many soldiers of a city and he will destroy the fence in-which- they -trust.” (Source: Kankanaey Back Translation)
• English: “A wise army commander helps his troops climb over a wall to attack a city that is defended by a strong army,
  with the result that they are able to get over/destroy the high walls that their enemies trusted would protect them.” (Source: Translation for Translators)