Tā yòng tōuliánghuànzhù de shǒufǎ cuàngǎile hétóng.
He used a bait-and-switch trick to tamper with the contract.
Tips
history
Popularized by 《红楼梦》 chapter 97 (Cao Xueqin, Qing dynasty): Wang Xifeng swaps Daiyu for Baochai at Baoyu's wedding — literally substituting a bride. It's also one of the 三十六计 (Thirty-Six Stratagems).
culture
Stratagem #25 in 《三十六计》: in ancient military use, 梁 and 柱 were metaphors for the main columns of an enemy formation — swap them out and the whole structure falls.