The below chapter provides a complete walkthrough for A Defiled Holy Mountain mission. It provides solutions for the challenges that you face in the main storyline of the game. Thanks to this, you will complete the game in the most optimal way. This mission ends in a boss battle with Ishida Mitsunari.
Send away the Kodama
This mission starts on a mead. There is a shrine here and a Kodama on one of the paths. Enter the mountain through the entrance next to the shrine. Inside, you will fight soldiers. In one of the caves, behind the fog, there is a yoki. After you have defeated it, you can collect several interesting items. Afterwards, walk outside and defeat the opponents.
As you go left, you will reach a location, where you have to defeat three locals and a yoki, who comes out of the fog. After the fight, open the chest, collect the loot and follow the path up. Along your way, you will have to fight several soldiers and ninjas. Once you activate the shrine, do not enter the cave and climb down, to send away a Kodama. Then, return here and make it over to the other side of the mountain.
Once you climb down the ladder, you will have to fight a raven. You can avoid the fight, if only you jump down onto the ledge below earlier. While you are here, climb down to the house that you can see underneath. Inside, there is loot and behind it, there is a Kodama. There is another Kodama on the ledge that you have to jump down onto, while you are climbing back up.
As you move on, you will run up into two paths between rocks. They lead to the same place, but it is a good idea to explore both of them, because you will find several interesting items, this way. On the first path, there are several soldiers and a ninja, whereas on the other, there is a fog that spawns Onyudo. After the battle, you can tip the ladder over, thanks to which you will unlock a shortcut to shrine.
After you enter the mountain, you will run into another fork. Take the left path. Along your way, you will have to watch out for a flame trap on the floor. Inside one of the caves on the left, there is a Kodama. After you exit, head left. Along your path, you will find another fork. By going to the left, you will find some loot, whereas the right path leads to the shrine. Watch your step, while walking into the building, because there is a yoki there.
After you have activated shrine, climb down the stairs. You will have to cross a bridge guarded by a raven and a local, throwing firecrackers. After you have defeated the opponents, go right, where you find a Kodama at one of the trees. Then, return to the bridge and climb down the ladder. At thend of the path, there is a building. Defeat the soldiers and enter. At the other end, you will find a hot spring.
Climb up along the path. Defeat the soldier and the archer. In the cave, the fog will spawn a n onyudo. After you have defeated it, walk out into a mead. There is an entrance to another cave, on the left. Inside, there is a shrine. Next to it, there also is a Kodama.
After you have climbed the stairs, you will notice a building. Inside, there is a ninja and another Kodama next to it. After you cross the door at the end of the stone tunnel, you will fight Ishida Mitsunari.