King Ka-thunk's Castle

King Ka-thunk's Castle (known in the British English Wii U version as King Kathunk's Castle), or , is the third castle level of Super Mario 3D World and its Nintendo Switch port Super Mario 3D World + Bowser's Fury and the ninth course in World 5. It is unlocked via completing Searchlight Sneak, and its own completion frees the purple Sprixie Princess who builds a Clear Pipe to World 6. This is the only castle level in the game that does not need to be unlocked with Green Stars.

Layout
This level starts on a platform with some Ka-thunks nearby, with some ? Blocks in sight. After navigating past some Chargin' Chucks and moving platforms, a nearby Warp Box takes the player to an area with some more Ka-thunks and the Checkpoint Flag. The player now needs to avoid Ka-thunks that come out from crevices in the wall, as well as more Chargin' Chucks. A nearby Warp Box brings the player to King Ka-thunk. After his defeat, a Warp Box transports the player to the purple Sprixie Princess and a Goal Pole.

Green Stars

 * Green Star 1: The player must activate the Green Ring and collect all eight Green Coins to reveal the Green Star.
 * Green Star 2: After the checkpoint, the second Green Star can be found inside a Ka-thunk. (See picture)
 * Green Star 3: The player must use the Cat form to climb a wall right next to the second Warp Box to obtain the Green Star.

Stamp

 * Not far from the second Green Star, the player must use the cat form to climb the wall next to the rotating Ka-thunks. The stamp is a Chargin' Chuck.

Names in other languages
König Klonks Kastell