The Yiga Blademaster Station can be found north of the Gerudo Canyon Skyview Tower and can only be entered when wearing the Yiga armor set.
Cave Location
The Yiga Blademaster Station is located at -2434, -1818, 0147, north of Gerudo Canyon Skyview Tower, west of Rakakudaj Shrine. The door is on the ledge behind the waterfall. To enter the cave, equip the Yiga armor set, then check on the door.
Cave Features
There is a Yiga Blademaster that you can talk to in the first room. He will explain the Blademaster exam and will mark the locations of the five frog statues on the map. He gives you five Mighty Bananas that you can use to complete the exam. See The Yiga Clan Exam for information.
After you make offerings at all five frog statues, come back to this cave and talk to the Blademaster to be permitted to go through the door behind him. Go through the door and open the two chests to get a Ruby and an Eightfold Longblade✨.
Before you go to the shrine, you can look at the north wall to see a short tunnel. Crouch and go through the tunnel, then look east to see this cave's Bubbulfrog in a niche in the wall.
Go back through the tunnel and go through the door behind the treasure chests to find Suariwak Shrine.