staggering blow meaning in English

惊天锤
闷棍
虚弱之锤

First , it was strictly platonic till nature intervened and an attachment sprang up between them , till bit by bit matters came to a climax and the matter became the talk of the town till the staggering blow came as a welcome intelligence to not a few evildisposed however , who were resolved upon encouraging his downfall though the thing was public property all along though not to anything like the sensational extent that it subsequently blossomed into
对于为数不少的居心险恶执意要使他垮台的人们来说，那可是个求之不得的消息。此事一直是个公开的秘密，然而并没有达到后来渲染成的那样耸人听闻的程度。既然他们二人的名字已经连结在一起，既然她已经公开承认他是她的心上人，还有什么必要从房顶上来向民众宣布呢？