變身赴洞 Assuming Both Their Forms
即便拔下一根毫毛，吹口仙氣，叫：「變！」變做個巴山虎，自身卻變做個倚海龍。假妝做兩個小妖，徑往那壓龍洞請老奶奶。這叫做七十二變神通大，指物騰那手段高。即便拔下一根毫毛，吹口仙气，叫：「变！」变做个巴山虎，自身却变做个倚海龙。假妆做两个小妖，径往那压龙洞请老奶奶。这叫做七十二变神通大，指物腾那手段高。
逐句解 Line by line
At once he plucked out a hair, blew on it a breath of immortal air, and cried “Change!” — turning it into Mountain-Straddling Tiger, while he made his own body into Sea-Reclining Dragon. Counterfeiting the two little imps, he went straight to Dragon-Crushing Cave to invite Old Grandma.
吹口仙氣 chuī kǒu xiān qì, blew a breath of immortal air, is the standard way of bringing a plucked hair to life — the breath is what turns matter into an actor. 那壓龍洞 nà yā lóng dòng, that Dragon-Crushing Cave, points with 那; 假妝 jiǎ zhuāng is counterfeiting, got up as. He has to be both messengers at once, so he splits the job between a hair and himself.
This is what is called: great is the power of the seventy-two transformations; high the craft of pointing at things and shifting them about.
A rhyming pair of lines closing the episode, the storyteller applauding his own hero — and the second line names the chapter. 騰那 téng nuó is to shift and manoeuvre, sleight of hand; 那 is read nuó here, standing in for 挪, to move, and has nothing to do with the pointing word it looks like. It is the same compound the chapter title carries as 騰挪. 指物 zhǐ wù is to point at a thing — and by pointing, change it.
The double transformation solves the problem the couriers created: to arrive at Dragon-Crushing Cave he must be both messengers, so he splits his presence between a conjured hair and his own body. The economy is characteristic — corpses hidden, shapes borrowed, errand continued without a beat lost. This is not concealment but impersonation: walking into the enemy's house wearing the enemy's face.
The couplet that closes the episode names the chapter's whole method. 騰那 — written 挪 in the chapter title, 那 in the text here — means shifting, transposing, sleight of hand, and it gathers everything Wukong does in these forty-seven passages into two characters. He wins nothing by force in this chapter. He wins it all by moving things, and himself, into places they should not be.