The drop rate on the eggsacs and the moonstone crystal shards is ridiculously low. Killing the queen allegedly gives 35 or so, but there were none on my corpse when I killed her. Which I doubt I'll be doing again.
Since each potion takes 5 sacs and each power coil takes 5 crystals, expect these to be super expensive...or just rarely made.
The river moss spawn is bugged, as it doesn't behave in the way Kyronix described.