Sleep

"Nothing is more dangerous to a cloudcatcher than the lack of some good shut eye. I've seen the Restlessness kill more cloudcatchers on ascents than any monster, natural terrain, or contagious disease ever has. It makes you sluggish. Sloppy. Go without it long enough and you start to see things that aren't there. Once your mind is untrustworthy and your reflexes slowed, you're as good as dead."

-Pathfinder Ramble Farseer of the Copperwalk Charter

Sleep, a condition of muscle relaxation and suspended consciousness, is observed to occur in all natural fauna across Oara save for the sentient, sapient races of mortalkind. Animals appear to have an innate ability to fall asleep and seem to do so at regular intervals. Some enter this state during sunfall while others do so during sunrise.
Due to what scholars call the Restlessness, mortalkind cannot enter this state naturally like other living organisms. Instead, a state of slumber must be induced through magic or medicine. In isolated places where the herbal ingredients required to fashion sleep medicine are unavailable, a sanctioned town healer or Tayvan cleric will use holy magic to induce sleep on the populace. Sometimes, these towns and villages on the fringes of the Citarii city-states have a population too big to be put to sleep by a solitary cleric. Therefore, it is a common practice for these populations to rotate designated groups of people to sleep.
In places where the Golden Chalice patented "Slumber" pills are commonplace and affordable, such as city-states, whole populations will induce sleep at night, except for those who might be employed during sunfall shifts as guards or otherwise. Having entire populations sleep at the same time is seen as a privilege of the urban regions by those in more rural settings.
Because the city-states contain much larger populations compared to the total population found in rural villages and hamlets, more Citarii are likely to experience sleep induced by the herbal pill Slumber rather than magically induced sleep. According to studies conducted by Conservatory scholars, those who sleep via magical means experience occasional dreams whereas those who use Slumber do not. Unsurprisingly, those who experienced nightmares on a regular basis while sleeping via magic often prefer the use of Slumber; however, this is not the case for all. In fact, many in rural areas prefer magically induced sleep specifically so that they may get a chance at receiving dreams.

"How ironic it is that sweet dreams seem to be a privilege of the poor rural bumpkin and not the wealthy middle class civilian or cloudcatcher of Teimor."

-Clerk Lahn of the Conservatory