This guide has been made for the sake of posterity in anticipation of these elements being changed or removed when the story of the game moves ahead. As such it contains spoilers and should not be read except by those who have already completed the investigation or those who habitually ignore warnings.

As Chapter Zero opens, the city of Kasa is locked down for mysterious reasons. While Coroners maintain a blockade, the rest of the Braided Shore is left to speculate on what might have happened. As rumours travel on the winds, a new wave of khelim wanderers appears, heralding a new age and beginning an investigation of their own. This guide will walk you through what they found and how they found it.

The first step a khelim takes towards investigating the blockade of Kasa takes the form of an apparently unrelated favour for the post warden. Upon encountering Post Warden Vastila along her route during the day, she will ask a khelim to undertake a personal delivery for her as she must be about her official deliveries. She will direct the khelim to the Bridge Sentry's house on the East side of the ravine at Char Cape Passage and hand over a knot describing a Shatran move for the khelim to deliver.
⠀
⠀

The dutiful khelim then heads to Char Cape Passage and meets the Bridge Sentry at the Rail Worker's Lodge on the East side of the ravine. He will be delighted to receive Vastila's latest move and ask the khelim to return to Vastila an item she left behind on her last visit. He will hand over Vastila's Bracelet, a rather valuable item.
⠀
Be sure to pet the sentry's cat.

The diligent khelim travels back along the main road to find Post Warden Vastila about her route during the day. Upon the return of her bracelet, she will admit that she's not much for jewellery but that the willingness to return it rather than to keep it or sell it confirms the khelim's trustworthiness. At this point she will formally invite the khelim to visit her friends at the old pavillion to the West of the mill in Kuro Orchard. While they all have occupations to keep them busy during the day, they can be found gathered there at night.
⠀
⠀
⠀
⠀
Returning Vastila's bracelet grants the achievement Vastila's Trust.

While the Night Bathers can be visited prior to any of the aforementioned events, they remain non-committal towards khelim visitors until such time as a formal invitation to join them has been extended. A khelim who visits them after having returned Vastila's bracelet will be greeted much more warmly. As the name suggests, the group can only be encountered at night.
Each of the bathers will give an introduction including a nickname and profession. At this time, Post Warden Vastila will encourage the khelim to gather information about the Coroner's Blockade of Kasa by visiting Siram Fields. While one cannot carry rumours, solid clues can be brought back to the bathers for evaluation.
⠀
⠀
⠀

Visiting the Night Bathers grants the achievement Nightly Meeting with New Friends.
⠀
Once a khelim is done dipping toes in the stream, it is time to get back on the road and head East to Siram Fields. One of the main gates to Kasa opens onto Kasa Heath and while the gates are currently closed and guarded, there's still a line of hopeful traders and travellers lined up outside. Here or elsewhere, the attentive khelim may find a clue about a group of children who are able to sneak past the blockade. These rumours should set the khelim's feet upon a path back to the ravine at Char Cape Passage.
⠀
⠀

⠀
Upon discovering the hideout of the Patterfoot Gang in Char Cape Passage, the footsore khelim will discover that they do indeed have access to Kasa and, furthermore, that they are offering pilfered Kasan items for sale. Many of these items are clues about what happened but three items are of particular interest to the investigation. These are the broken lute, the mysterious feather and the marble and cobalt coloured knot message.
⠀
⠀
It may take a number of visits for the worthy khelim to finally obtain each of these items but each one, upon examination by the Night Bathers, will reveal new information about the mystery. Purchasing any one of these special items grants the achievement A Clue?.

⠀
Upon collecting any or all of the clues, the khelim may revisit Vastila and her friends at the pavilion in Kuro Orchard to share what has been found.

Vastila will direct the khelim to show the broken lute to Miller Yeget who will identify it as Singer's Broken Lute.
⠀
⠀

Vastila will direct the khelim to show the mysterious feather to Hav Stormbegger who will identify it as a Ruffled Sefra Feather.
⠀
⠀

Vastila will direct the khelim to show the marble and cobalt coloured knot message to Archivist Tisleth who will identify it as a Coroner Custodian's Report.
⠀
⠀

⠀
Once the industrious khelim has gathered enough clues, Farmer Ravda will declare that she has an announcement to make. She has unravelled much of the mystery and is prepared to explain her theory to the assembled night bathers. Read the left image and then the right.
⠀
⠀
Hearing this speech grants the achievement The Kasa Incident Explained.

⠀
Finding a Singer Rosary
⠀
An observant khelim will have noticed that an entry from Singer's journal has been hung upon the pavilion itself. Information from various sources reveals that Singer attached the entries of his journal to homing pigeons in the hope of information reaching the Night Bathers but that most of them didn't complete the trip due to being hunted down by official falcons from Kasa. These entries are known as Singer's Rosary and they can be found by examining the corpses of pigeons around the Braided Shore. While collecting them is not necessary for advancing the investigation, finding one of them will grant the achievement Singer's Rosary and finding all of them will grant the achievement That Dark Night in Kasa. Not counting the entry at the pavilion, there are twelve in total to be found.
⠀
⠀

⠀

⠀

⠀

Be sure to collect these achievements while they're still available as there's no telling what will happen to them once the story has moved on.

If you find an error in this guide, please let me know!
⠀