Main mission: The frenzied Blaze

Follow the path to a ladder, climb it to find the first shrine. Use rubble to proceed upwards, then jump down. Search the corpse ahead, using water buckets to avoid flames. Encounter 3 enemies (2 inside, 1 outside a house). Go around the house (avoiding fire) to a fork; go right for now.

Search a body and enter a nearby house for a sub-boss. Beyond this, you'll find blue flames that burn health rapidly.

Return to the fork and go left. Kill enemies inside and outside another house. Go around this house from the right to find a Gaki and the 1st Kodama behind it.

Follow the path left of the house to a gate leading back to the shrine. Go around the house from the other side to find a ramp.

In this area, defeat a skeleton soldier, wheelmonk (which extinguishes nearby blue flames), and a disguised Koroka.

Return to the broken well before the wheelmonk fight. Go to the nearby house, defeat the dwellers inside, and go around the house to beat a Gaki and Rokurorubi.

Follow the path to a dark realm. Fight a large skeleton soldier and Rokurorubi. Open a gate back to the wheelmonk area (a minor sub-boss blocks it). Use a ladder near this gate to reach rooftops, drop water on blocking flames, and proceed. Fight the Koroka causing the dark realm. After beating it, do NOT open the gate.

Go left to find 3 white butterflies (interacting with all gives a trophy). Open the gate, and to its right is the 2nd Kodama.

Follow the path to the 2nd Shrine. Beat Dwellers, then go through a hole in a wall to fight an Ubume. Climb a ladder to the roof. From the ladder, look left for the 3rd Kodama on a connected roof.

Drop water on flames blocking your path. Go near the castle but don't enter yet. Walk around the outer part of the castle on the right to find the 4th Kodama in the corner.

Kill the Rokurorubi beyond the flames. Proceed to its right to find more white butterflies (you'll be attacked by a human enemy).

Enter the castle-like building for a sub-boss: a blue fire wheel monk. Proceed through the open path to a gate back to the shrine. Use rubble at the back of the castle to reach the roof and find a Sudama.

Find a ladder and descend to meet Yasuke. Speak to him to have him join you.

In the area directly ahead of Yasuke is a dark realm. Defeat a skeleton soldier, wheelmonk, and Koroka. Walk around the house avoiding blue flames until you find a ladder. Walk along the roofs to reach the blue flame wheel monk. Killing it removes the flames and the dark realm. Go around the house to find a dweller and the 5th Kodama.

Return to where you met Yasuke. Go left and enter a house with a Gaki, skeleton soldier, and Rokurorubi. Find the 6th Kodama in the corner.

Advance out the path to a dark realm (ignore for now). Follow the path to a room with paper doors; break them to fight a sub-boss Ubume. Open doors back to the 2nd shrine.

Follow the path, defeat a Rokurorubi, then go straight to a fork. Turn left for a hotspring. Go right to another fork. Turn left to beat enemies in and around two houses. Go around the house to find a Sudama. Use nearby water buckets to protect yourself and dive into the house on fire to open a chest. Exit to the right to find a ladder.

Climb the ladder to the roof. Go to the roof on the right, then straight towards a glowing yellow area with a ladder going down. Descend and fight a skeleton soldier. In a corner is the 7th Kodama.

Return to the fork and go down the other path to a sub-boss Koroka.

Proceed into the dark realm. Beat an Onyudo, skeleton soldier sniper, and the blue flame wheelmonk to remove blue flames (this does not remove the dark realm). Find a 3rd shrine. To its right is a path with a skeleton soldier and an Ippon datara.

Kill them to remove the dark realm. Open the chest in the corner. Opposite it are the last 3 butterflies. Behind where the wheelmonk was is a gate; open it.

Use the shrine and open the gate. Yasuke will leave your party. In front is the boss room. Before entering, look left for the 8th and last Kodama.

Fight the boss, Kasha.