Location: There will be an obvious breakable wall which leads to a clam with some Teeth. To the right of this clam is another breakable wall which leads to a Radula, which is accessible by invisible platform.
Location: After the Colossal Ruin comes the third switch. Hit it, follow the new path and cross the bridge. To the right is a platform and a Pig Snouts. Shoot the snout, follow the revealed path, smash a bit of congealed ruin and find a keyhole. Go through it, follow the platforms (visible and invisible) - there is the Radula.
Type: Quiz Radula
Question: "We welcome the arrival of a phantom at sunset, only to rue its departure at sunrise. What is it?"
Answer: Dreams (wrong answers: May flies, Night Phlox, Hope)
Question: "What warms like the summer sun, and heats like a blazing fire, but does not burn?"
Answer: Blood (wrong answers: A serpent's tongue, A spring rose, Molten Lava)
Question: "I talk, but I do not speak my mind. What am I?"
Answer: An Actor (wrong answers: A politician, A puppet, A parrot)
Question: "What is so delicate that when you say its name it is broken?"
Answer: Silence (wrong answers: A heart, A vow, Love)
Scroll of Happy Times
Location: In the second room containing Samurai Ink Wasps: from the entrance to the room, hop over the chasm and take a left, then jump up. The Radula is down a path.
Location: Past the caves and the fans, the player will come to a green cave. Find the first Fish Switch past a breakable wall and flip it. Across the main section of this room is a Keyhole - not the one which is under a stomping statue, another one. Follow this Keyhole's tunnel, and the player will find the Radula.
Type: Survival Radula
Enemies: Cannon Crab, Shield Madcap
West Peak Prison Village
Location: After the giant frog opens up the path, there are two breakable walls. Follow the one on the right (the main path) a short ways until the player sees some Teeth on the ground. There is a Keyhole snugged in that alcove. Follow that tunnel and the player will reach the Radula.
Location: At the gate of the castle, turn right and find a breakable wall. Through there lies a mushroom; bounce up and there's the shell.
Type: Quiz Radula
Question: "What comes next in the sequence 1 3 4 7 11"?
Answer: 18 (wrong answers: 13, 17, 21)
Question: "What always runs but never walks, often murmurs, never talks, has a bed but never sleeps, has a mouth but never eats?"
Answer: A river (wrong answers: An inveterate gossip, A restless child, A suicidal insomniac)
Question: "I never was, am always to be. No one ever saw me, nor ever will. What am I?"
Answer: The future (wrong answers: A promise, Divinity, Blithe spirit)
Question: "At night they come without being fetched. By day they are lost without being stolen. What are they?"
Answer: Stars (wrong answers: River rats, Garbage Collectors, Cockroaches)
Waste Wing Part 1
Location: In the large room with the three sets of balancing platforms, the player has to pull a Switch to proceed. Upon pulling this switch, turn around and go to the previous platform. From there, the player can now Float across a couple of vents to find the Radula.
Question: "If you break me, I do not stop working; If you lose me nothing will matter."
Answer: Heart (wrong answers: Whip, Horse, Key)
Question: "Feed me I live; give me a drink and I die."
Answer: A fire (wrong answers: A skink, A cactus, An alcoholic)
Location: After defeating the Doll Girl, follow the winding path opposite the way the hand in the painting is pointing and destroy the obstruction blocking the keyhole. Once inside take the first right to find the room.