Now as the old saying has it: "Where the mountain is high, there must be monsters; where the ridge is sheer, there spirits are bred."

A proverb used as a scene-change — the narrator's favourite way of swinging the camera off the pilgrims and onto whatever is watching them. 怪 (guài) and 精 (jīng) both mean "monster, sprite" and are near enough interchangeable. The saying blames the terrain itself: high mountains breed monsters the way damp breeds mould.

Sure enough, on this very mountain there dwelt a fiend, and the Great Sage's departure had startled it into motion.

果然 (guǒ rán), sure enough — the proverb is proved on the spot. This is the White-Bone Demon, 白骨精, whom the chapter title calls the Corpse-Fiend, 屍魔. The narrator will give her neither name until her bones are lying on the path. And note the trigger: 去時, the moment Wukong leaves. The machinery is showing.

Treading a dark wind up among the clouds, it caught sight of the elder seated on the ground and, unable to contain its delight, cried, "What luck! What luck!

陰風 (yīn fēng) is the cold ghostly wind demons travel on in this novel, as standard an issue as a witch's broom; the 著 of 踏著陰風 is zhe, keeping her up on it. Her cry is 造化 (zào huà), which literally means "the making and the transforming" — the workings of creation — and is used, exactly as English uses "my luck!", for a windfall dropping into your lap. 不勝歡喜: more joy than she could carry. (不 rises to bú before the falling tone of 勝.)

"For years now everyone has told how the Tang monk of the Eastern Land goes to fetch the Great Vehicle — how he is the incarnation of Golden Cicada, an original body ten lifetimes in the cultivating: whoever eats but a morsel of his flesh shall have long life, life everlasting.

Here is the premise the whole novel runs on, recited by the villain like a recipe. Tripitaka was 金蟬子 (Jīn chán zǐ), Golden Cicada, a disciple of the Buddha demoted into mortal birth, and this body is the far end of 十世修行, ten lifetimes of self-cultivation. One mouthful and you live forever. That is why every demon on the road west wants the identical thing, and why the pilgrimage is, structurally, a very long escort mission. Two readings: 乘 in 大乘 is shèng, the Buddhist "vehicle" that renders the Sanskrit yāna, never chéng, "to ride"; and the 子 of 金蟬子 is the honorific zǐ. The doubled 長壽長生 takes 長 as cháng, "long", not zhǎng.

"And today, truly, he has come!"

真個 (zhēn gè) is plain spoken emphasis — really, actually, truly. Six characters, and the monologue lands on the appetite underneath it: they have been talking about him for years, and today he is here.

The fiend pressed forward, meaning to seize him at once — but seeing two mighty generals guarding the elder to left and right, it dared not close in.

She goes straight for him, and stops. 攏身 (lǒng shēn) is to close the gap, to get within arm's reach — and she cannot. 員 (yuán) is the counter reserved for military officers, so 兩員大將 is "two officers of general rank"; that 將 is the noun jiàng, not the jiāng that fronts an object. 護持 (hù chí): to guard and hold up. Which raises an obvious question, and the narrator is about to ask it on our behalf.

And who, you ask, were these two generals?

The storyteller turns to the room. 他說 here is not "he said" but something nearer "you'll be asking" — a live performer fielding a question from the audience. (將 is jiàng again.)

They were Eight Rules and Sha the Monk.

And the answer deflates the question beautifully: the two mighty generals are the pig and the sand-monk. 八戒 (Bā jiè) means "Eight Prohibitions", the eight monastic rules he is supposed to keep and largely does not; 沙僧 (Shā sēng) is simply "the Monk Sha", Sha Wujing. The build-up gets a fanfare. The reveal gets two nicknames.

Now Eight Rules and Sha the Monk had no great powers to speak of; but Eight Rules had been Marshal of the Heavenly Reeds, and Sha the Monk the Curtain-Raising General, and the martial aura of those offices had not yet wholly leaked away — and so the fiend dared not close in.

The explanation is one of the driest jokes in the chapter. These two have 沒甚麼大本事 — no real ability worth mentioning. What holds the demon off is their curriculum vitae. Bajie was once 天蓬元帥 (Tiān péng yuán shuài), Marshal of the Heavenly Reeds, commanding the celestial navy; Sha Monk was 捲簾大將 (Juǎn lián dà jiàng), the general who rolled up the screen at the Jade Emperor's throne. Both were sacked. But 威氣尚不曾泄 — the aura of the office has not yet leaked away. It is the deference a room still shows a retired colonel. (甚 is shén here, the "what, any" of 甚麼.)

Said the fiend, "Let me toy with them a while, and see what comes of it."

戲他戲 — play him a play — is the demon announcing her method before she uses it. 戲 (xì) is play, sport, and also theatre; the chapter's own title uses it, 三戲 (sān xì), thrice toying with Tripitaka. She is not planning a fight. She is planning three performances. 且 (qiě) is "for now, just"; 看怎麼說, see what comes of it.