There is 13 Rot to collect in Rusu Mountain. You will reach this part of the game beyond Taro’s Tree.
The first Rot is available north of Gorge Warp Stone. From the Warp Stone, head to the left until you see glowing lanterns. Clear the area and then turn right to find a Rot under a stone. You have to use your Rot to move the stone.
You will find the Rot 2 after the Forest Tear by the deer statue. Continue along the path until you reach the wooden arch after a muddy slope. Just before the wooden arch, climb up the ledges on the left. You will find a Rot near the stone slates.
This Rot is available just after the Ruins warp stone (fast travel point) as shown in the below image. Here you have to drop down a series of ledges to reach a platform along the cliff. In one of the platforms, you will find a Rot near a glowing stone slate.
This Rot is available after Ruins warp stone. After climbing up all the ledges, go left instead of the main path. Use Rot to carry stone over to a high platform where a Rot is under a stone pillar.
This Rot is available after learning the Bow ability. You’ll reach an area with archery challenges. Over to the left is one of these challenges where a blue pot is hanging from a tree. Shoot it for a get a Rot
Clearing the corruption from Rusu’s house, you will get three Rots.
Head inside Rusu’s house. The next Rot is trapped inside a drawer on the right.
Go to the west side of Rusu’s house where you will find an untilled field. Shoot the wooden wheel attached to two blue targets and then activate the tear. Move the Rot on the field to till it, making sure to go over the purple glowing spot. Use pulse on the purple glowing vegetables to find the Rot.
After clearing Rusu’s house of corruption, head south to an area with an owl statue. Just before the small pond, you will find a bed of orange flowers. There’s a Rot running around with a flower. Hit the running rot with an arrow and then pulse it.
Available after acquiring the Bow ability. Head back to the Gorge warp stone (fast travel point). You will find a small island. Shooting the blue flower with an arrow to reach the island. You will find a Rot near stone slabs.
From the “Gorge” fast travel point, swim in the river along the left cliff towards the waterfalls. To the left of the waterfalls, you will find a Rot on a platform.
After Ruins warp stone you’ll reach a broken wooden bridge. Go to the right before the broken bridge and jump to a higher ledge. Follow the ledge around the corner to find the Cursed Chest.
After Ruins warp stone (fast travel point) on way to Rusu’s house you will find a cliff where you can follow the path to the left or go around the cliff to the right in clambering style. Go around to the right and into a small cave to find the Spirit Mail.
There are 6 Hats available in the Rusu Mountain area
#1 Hat: Bird’s Nest
After Ruins warp stone you’ll reach a broken wooden bridge. Go to the right before the broken bridge and jump to a higher ledge. Follow the ledge around the corner to find the Cursed Chest. You need to complete the Cursed Chest’s objective and then open the chest again to receive the Bird’s Nest Hat.
#2 Hat: Whirly Bird
Available after getting the Bow ability. You’ll progress to an area with some archery challenges. Head down to the left of the tree with brown leaves and go up the steps to a platform. Whirly Bird Hat is in the cart.
#3 Hat: Rusu’s Mask
You need to complete all four archery trials just after getting the Bow ability to get this hat.
#4 Hat: Squash
Go to the west side of Rusu’s house where you will find an untilled field. Shoot the wooden wheel attached to two blue targets and then activate the tear. Move the Rot on the field to till it, making sure to go over the purple glowing spot. Use pulse on the purple glowing vegetables to find the Rot. You will get Squash Hat after collecting the Rot
#5 Hat: Flower
After clearing Rusu’s house of corruption, head south to an area with an owl statue. Just before the small pond, you will find a bed of orange flowers. There’s a Rot running around with a flower. After collecting this Rot, you’ll get the Flower Hat.
#6 Hat: Feather
After clearing Rusu’s house of corruption, head south to an area with an owl statue. You will find three cogs on the right. First, use the Rots to pull the middle gear into place and then hit the lower most cog three times to rotate the mechanism and bring the platform to the correct height. Jump over the platform up to a higher area and then pass the gap using the lift. On the other side are two flowers you need to use arrows on to get across. Once you do, there’s a chest with the Feather Hat inside.
#1 Flower Shrines
Along the main path, you’ll come across a deer statue/Altar, where you need to use your mask. After this create a Rot Cloud from the plant in front of the large Altar and use it to clear the corruption on the left side. The Flower Shrine is at the end.
#2 Flower Shrines
After getting the Bow ability, you’ll find an area with a few archery trials. One of the trails is timebound. At the starting position of this trial, there are few stones slabs with corruption. You can go uphill on the right and shoot the crystal on the tree to form a plant. Create a Rot Cloud to clear the corruption. Clear the corruption to find a Flower Shrine.
#3 Flower Shrines
Head south after clearing Rusu’s house of corruption to find an owl statue. On the left of the owl statue is a path block with corruption. Hit the crystal on the owl statue to form a plant. Create a Rot Cloud using the plant and clear the corruption on the left side. Go through the tunnel and clear all corruptions and then cleanse the Flower Shrine ahead.
Descend the mountain after completing the archery challenges along the main path. After lowering the drawbridge, turn right to find the Meditation Spot on a platform. To get there, use the Spirit Bow to shoot the glowing flower on the tree.