分派龍兵 Positioning the Dragon-Troops
那行者領著龍兵，不多時，早到號山枯松澗上。行者道：「敖氏昆玉，有煩遠踄。此間乃妖魔之處，汝等且停於空中，不要出頭露面。讓老孫與他賭鬥，若贏了他，不須列位捉拿；若輸與他，也不用列位助陣。只是他但放火時，可聽我呼喚，一齊噴雨。」龍王俱如號令。那行者领着龙兵，不多时，早到号山枯松涧上。行者道：「敖氏昆玉，有烦远踄。此间乃妖魔之处，汝等且停于空中，不要出头露面。让老孙与他赌斗，若赢了他，不须列位捉拿；若输与他，也不用列位助阵。只是他但放火时，可听我呼唤，一齐喷雨。」龙王俱如号令。
逐句解 Line by line
The Pilgrim, leading the dragon-troops, in no long time reached the Withered-Pine Torrent on Roaring Mountain.
Back to Roaring Mountain with an ocean behind him. The journey that took the dragon kings a bell-stroke to assemble takes Wukong no time at all to lead -- the novel never lingers on travel when a cloud is involved.
The Pilgrim said: ‘Gentlemen of the House of Ao, I have troubled you to come from afar.
敖氏昆玉 is elaborately polite. 昆玉, literally elder-brother-jade, is a courteous way of referring to another man's brothers, so this is something like "honoured gentlemen of the House of Ao." Wukong, who three chapters ago robbed this family's palace, has excellent manners when he needs something.
This place is the demon's own ground; do you all stay up in the air, and do not show yourselves.
The instruction: stay in the air, out of sight. 不要出頭露面 -- do not stick your heads out or show your faces. 露 is read lòu here, the everyday "show" sound, rather than the more literary lù. It is a phrase you would use to tell someone to keep out of sight, and it is still current.
Let old Sun do battle with him: if I beat him, there will be no need for you gentlemen to make the capture;
The terms, and they are proud ones. If I win, you are not needed. Wukong is borrowing an army and forbidding it to fight.
and if I lose to him, there will be no call for you gentlemen to reinforce me either.
And if I lose, you are still not needed. He has ruled out reinforcement in either direction. The dragons are here for exactly one thing.
Only when he looses his fire, listen for my call, and all together spout your rain.’
Which is this. 他但放火時 -- the moment he looses fire, wait for my call, and all together let the rain go. One trigger, one response. The precision matters, because the next two passages turn entirely on whether the cue comes at the right moment.
The Dragon Kings did all as he commanded.
俱如號令, all followed the command. Four sovereign kings of the sea, taking orders from a monkey, without a word of objection recorded.
Wukong deploys his borrowed army with real care, and the care is all about timing. The dragons are to stay hidden, take no part in the fight whatever the outcome, and act on one cue only: fire, then his call, then rain, all at once.
The pride in it is worth noticing. He has just gathered every drop of water in the world and his first instruction is that none of it is to help him fight. Win or lose, the duel is his. That is admirable and it is also exactly the trait Bajie diagnosed ten passages ago -- the man cannot break off a fight -- now dressed up as a battle plan.