<span class="chinese-post-title">圍魏救趙</span> Besiege Wei to Rescue Zhao from the <span class="chinese-post-title">三十六計</span> Thirty-Six Stratagems

圍魏救趙

共敵不如分敵，敵陽不如敵陰。

"When the enemy is too strong to attack directly, then attack something he holds dear. Know that in all things he cannot be superior. Somewhere there is a gap in the armour, a weakness that can be attacked instead."

Quoted from Chinese Classics and Translations