一個金蒼蠅 A Gold Fly In The Face
即變做一個金蒼蠅，飛去望老魔劈臉撞了一頭。那老怪慌了道：「兄弟，不停當，那話兒進門來了。」驚得那大小群妖，一個個丫鈀掃帚，都上前亂撲蒼蠅。即变做一个金苍蝇，飞去望老魔劈脸撞了一头。那老怪慌了道：「兄弟，不停当，那话儿进门来了。」惊得那大小群妖，一个个丫钯扫帚，都上前乱扑苍蝇。
逐句解 Line by line
At once it became a gold fly, which flew straight at the old fiend and butted him full in the face.
劈臉 — splitting the face — is still the ordinary way Chinese says something came at you head-on. Gold, because Wukong cannot resist, and because a plain fly would not have been noticed.
The old monster panicked. "Brothers, this is not right. That thing has got in through the door."
當 is dàng, the departing-tone band the dictionary glosses as 事理合宜也, matters being fitting and proper — so 不停當 is things not sitting right. 那話兒, that thing, is the vernacular for a name you would rather not say aloud.
So startled were the whole crowd of demons, great and small, that every one of them snatched up a fork or a broom and rushed forward swatting wildly at the fly.
驚得 takes the light de, the same shape as 諕得 two scenes back — startled so badly that. 丫鈀 is a forked rake, and the picture is precise: a hundred armoured officers in dressed ranks, flailing at a housefly with farm tools.
The image is the joke and the joke is the argument. When the chapter first showed us this hall, it held a hundred officers in helm and mail with the killing air coming off them in waves. Here they are, brooms out, chasing a fly round it.
Chinese storytelling loves this reversal and this book leans on it harder than most: the terrifying thing is only terrifying until somebody refuses to be frightened of it. Wukong has not fought anyone yet. He has simply made the demons behave like what they are, which is a household with a pest problem.