Consult this map for this part:

This is an underground entrance to the Gifu Castle. You'll have to kill the 2 giants before you can continue.

The next area has a spiral staircase and 2 boxes, but you can only open the red one, only Ekei can open the other one.

• Gift Item: Crystal Ball

Take the stairs to the surface. If you have played Onimusha Warlord, you probably recognize this castle and the layout remains the same. Now go to a door at the opposite side of where you just came out.

One of the following scenarios is triggered depending on your route:

After the cutscene, go inside the castle. There are archer demons on the second floor, the only way to reach them is using bow, or you can simply ignore them. Next, pick up the 2 treasure boxes:

• Map: Gifu Castle Keep Tower Map
• Gift Item: Incense

Enter the side door first on your left. In the room, you'll find a Magic well and a number-puzzle lockbox.

• Key Item: Bronze Mask (Right) - (Solution: 1st row: 6-1-8, 2nd row: 7-5-3, 3rd row: 2-9-4)

Leave the room and enter the main door. Here, Ekei is struggling with the demons, so you should help him. Once you cleared the area, open the box:

• Item: Herb

Enter the red door (the smaller door is locked). Here you'll see another trick box:

• Item: Power Jewel - (Solution: Bottom Right, Right Top, Top Left) use it immediately unless if are completing no jewel achievement.

Continue to the next area. Ignore the green-sealed door for now and save your game at the Magic Mirror. Then, enter the next door (after the Magic Mirror).

There is a treasure box containing a history book:

• Gift Item: History Book Vol. 1

Enter the door under the staircase next to the treasure box. Inside, you'll find a ghost who asks you to bring him the Purifying Charm. Then, there is a yellow book on the shelf behind the ghost.

• File: The Demon's History

Leave the room and take the staircase to the second floor. In this room, either Ekei or Kotaro will join the fight depending on the route you chose.

Now take the door to your left. Then follow the path and enter the other door. Inside, you'll find a treasure box and the "Purifying Charm".

• Item: Herb
• Key Item: Purify Charm

Leave the room. You'll see Magoichi is fighting demons on the first floor. You cannot do much so just ignore him and backtrack to the ghost room, then use the Purifying Charm to release his soul. In return, he'll drop another key item:

• Key Item: Bronze Mask (Left)

Go back to the green-sealed door and use both "Bronze Mask" to unlock the door.

Once you regained control, kill the 2 demons to remove the barriers, then pick up a treasure box in front of the skeleton wall:

• Item: Medicine

It is not much of a fight, you just have to keep hitting him until Oyu shows up and saves you. There are 2 ways to deal with him.

1. Use your sword and keep hitting him until you both cross swords.
2. I prefer this method because it is less risky by using the spear secret move "Down + Up + Attack", then "Attack". Most of the time, he'll be unable to retaliate because he'll be busy blocking your attacks.

Follow the path and go up the ladder, then talk to Oyu she'll give you the "Faith Orb" and 3 scenarios happen consecutively:

• Key Item: Faith Orb