Should I use the River of Light in this cavern?
Hint 1 of 5:
Not initially. That is, not upon first visiting the cavern and talking with
Londie.
Hint 2 of 5:
You can certainly try the River of Light, at least to visit the Cepheid Road
and the Plain of Sand.
Hint 3 of 5:
Nothing much will happen until you have accomplished several other things
first.
Hint 4 of 5:
You don't really want to try and do much more for the Cepheids while they are
still in their drugged condition.
Hint 5 of 5:
The most important thing is to turn off all of the oxygen generators.