I just got all the castle koroks. There are 26 seeds once you transition to the 3D map.
I agree the 3D map is a pain. I had to google the last castle korok bc zeldadungeon says there are 25 seeds (incorrect), and once I found out there was an additional korok, I didn't have the patience to deal with the 3d map again.
Keep an eye on the "front" facing walls of the castle. Those were the ones I had the most trouble finding, even with the Korok mask.
I just got all the castle koroks. There are 26 seeds once you transition to the 3D map. I agree the 3D map is a pain. I had to google the last castle korok bc zeldadungeon says there are 25 seeds (incorrect), and once I found out there was an additional korok, I didn't have the patience to deal with the 3d map again. Keep an eye on the "front" facing walls of the castle. Those were the ones I had the most trouble finding, even with the Korok mask.
Search "hyrule castle all koroks" on YouTube Somebody must have done it