Islets: 60 upgrades, treasure hunt, Stone Witch revival and letter events

The total is 60. Buy Upgrade Markers for 2,500 and compare each island's collected/total count in Sky City. Collecting missing items after finishing the game is fine.

See the 60 upgrade locations table for rooms and actions. Distinguish Northstable: 17, Inverness: 16, Wolfpine: 15, Eastwright: 10 and Cinder: 2, and count the three papers in the same hidden room individually.

1. Check missing counts per island and choose an island whose missing count is not zero.
2. Return beyond heights, lower floors, remote switches or beams after acquiring abilities.
3. If you reach a marker's room without obtaining it, check entrances from adjacent rooms and paths after island connections.
4. Once you have all 60, head to Cinder's Final Gate.

The table records landmarks and checked routes. It explicitly identifies first-pickup screens or nearest shrines still under review and untested minimum abilities. It is not a complete coordinate map.

Begins by choosing the card offering a strange letter. Do not simply visit the final location first; read the Post Box and each letter in order.

1. Choose the card reading Receive a strange letter in your post box.
2. Read the first letter in Sky City's Post Box.
3. Slam at the large gravestone southeast of Spirits Landing and read the letter below.
4. Return to Tomb of 1000 Spirits' boss room and use Wall Climb for the upper-central hidden path. Read the next letter.
5. Return to the first Grave Crawler room. Inspect right of the Double Jump statue and complete the final objective.

Choose the Something happens in Forgotten Rots event instead of a normal card. Then return to Stone Witch's battle room and check the scene.

Do not infer a permanent missable from the heading alone. Check whether you chose the card and returned to the location. Deleting the original save or starting over is not universally required.

Check Snoot's letters arriving after events such as defeating Runaway Plant. After reading the shop invitation, return toward the gardens and check whether the shop is available.

There is also post-ending shop guidance. If the event has not triggered, advance the story and reread mail. No earliest trigger is guaranteed across every platform.

GreyBird sends a letter after Forgotten Grave is defeated. Read it in the Post Box, then return northeast of Spirits Landing to visit the spirit.

The defeated boss's room and the new spirit's location differ. Check Spirits Landing as directed by the letter instead of continually returning to Rainy Plains.

Drop into the hidden area and strike the vending machine. Do not stop at the first can; keep checking until currency appears. This is an additional action for Getting Thirsty.

Look for the rain-loving character near the port and in the rainy northeastern area of Rainy Plains. Finding the first location alone does not count as finding both.

1. Inspect the wall side near the port.
2. Climb to the rainy northeastern area and visit the second location.
3. Check that Loving the Rain unlocks.

After obtaining Shift Arrows, return to the Tomb of 1000 Spirits room. Prepare the movement arrow before toggling the switch, then enter while the opening is available.

1. Prepare and aim Shift Arrow.
2. Toggle the switch.
3. Quickly move to the arrow's position and dodge through toward the pit.
4. If upgraded range reaches, also check whether you can pass directly with the movement ability.

G numbers are this guide's own checking labels. Pickups display Ship Part, the same components called Gear at the upgrade shop. Combine positions on the connected-island map with shrines, platforms and challenge landmarks.

These actions are routes the original guide confirmed through PC play. This is not a verified table of minimum abilities for all six. A video route using Wall Climb or Double Jump does not guarantee another ability can replace them.

Combine Cloud Arrows clouds with climbable log sides. In shafts with spiked walls on both sides, move onto safe surfaces of chain-hung logs instead of climbing the walls themselves.

Later, a horizontal section has spikes on its ceiling and floor. Use the central hanging log as a waypoint and jump to the next. At the final depression, climb slightly higher ground on the right to collect the part.

Spending five parts on the first and second ship upgrades is separate from exploring for the additional sixth. This difficult section is not required before the first ship upgrade.

After the Stone Witch battle in Forgotten Rots, collect the propeller-shaped component. The original PC display reads Ship Motor. It is used for the second ship upgrade, not counted as a seventh Ship Part.

Collecting Motor does not teach ground Wall Climb. Check delivery to the ship specialist separately from acquiring ground abilities.

Each opens for 100 credits. Paying Your Dues requires all five; this differs from Final Gate after 60 upgrades.

Paid blue vertical gates and black return doors are different. In Inverness, the source confirmed a gate displaying a 100 payment beyond a black door. The other four unconfirmed payment locations are not inferred from different map icons.

The source directly viewed the display at 6:13–6:18 in public PC gameplay. The other four locations and payment inputs across every platform remain incomplete.

Complete the story and collect 60 upgrades, then visit the door above the teleport point near Cinder Island's port. Check The Mystery Beyond and select Boss Rush from the main menu.

This guide does not guarantee that story completion alone unlocks it on every platform; it assumes Final Gate has also been opened.