Crumble Cavern

Crumble Cavern is the first secret level of Autumn Heights in Donkey Kong Country: Tropical Freeze and its Nintendo Switch port of the same name. It is unlocked after finding the secret exit in Sawmill Thrill.

The music that plays in the level is an arrangement of "Cave Dweller Concert" from Donkey Kong Country, which also played in cave levels. David Wise is credited for composing both tracks.

Overview
At the start of the stage, just past two Tucks and a Cheesy Chester, there is a vine leading down. As the Kongs proceed further into the level, they will encounter teetering platforms, controlled by two waterfalls that alternate on both sides, and more vines. After encountering more Cheesy Chesters near the giant cheese wedges in the background, the Kongs will enter a series of Barrel Cannons, some of which require the player to manually launch to the next one with timing.

Past the first checkpoint after the Barrel Cannons, there is a DK Barrel on a ledge reachable using a vine, which snaps and falls once Donkey Kong makes contact with it. More weak vines are found later on, which the Kongs must use to traverse the bottomless pit. After that, the Kongs will enter another sequence of Barrel Cannon blasts, except this time, at certain points, they can choose which Barrel Cannon at which to launch. Regardless of which paths they take, the Barrel Cannons lead to the next checkpoint.

After jumping across more teetering platforms and vines and launching from two more Barrel Cannons, giant stalactites will start to fall from above and break the platforms. While outrunning the stalactites, the Kongs will climb several more weak vines and find Barrel Cannons attached to idle stalactites. Upon entering one of these, the stalactite will start to collapse and drop, meaning the Kongs must time their launch to the next Barrel Cannon before it falls into the pit. The Kongs will eventually enter a Barrel Cannon that spirals up and around a large spire. The Slot Machine Barrel is at the top, and completing the level will unlock the second secret level, Rodent Ruckus.

K-O-N-G Letters

 * K: Above the first Fluff between two vines.
 * O: Above a Hootz between two weak vines halfway between the first and second checkpoints.
 * N: Obtained right after launching from the first Barrel Cannon attached to the stalactite.
 * G: While inside the Barrel Cannon revolving around the spire, several columns of Bananas will appear, with the letter "G" in the middle. The Kongs must blast themselves up at the right time before it moves past it to collect it.

Puzzle Pieces

 * 1) On a platform, which can be reached using the vines above the first teetering platform.
 * 2) Just underneath and to the right of the teetering platform with the Tuff Tucks, there is a Barrel Cannon leading to a Bonus Area. Collecting all of the Bananas here within the time limit will reward the Kongs with the Puzzle Piece.
 * 3) Using the aforementioned Tuff Tucks, Donkey Kong must throw it at the sack suspended in front of the giant cheese wedges to reveal the Puzzle Piece.
 * 4) Halfway through the first series of Barrel Cannons, there are five columns of Bananas lined up next to each other. The Kongs must blast themselves up with the Barrel Cannon to collect them; collecting them all reveals the Puzzle Piece.
 * 5) While inside the horizontally moving Barrel Cannon behind the rock wall with holes, the Kongs must launch themselves at the uppermost Blast Barrel (the one without the skull marking), which leads to another Bonus Area with the Puzzle Piece.
 * 6) Above the Pointy Tucks past the second checkpoint. It can be reached using the nearby vines.
 * 7) Similar to the fourth Puzzle Piece, there are seven Banana columns above a moving Barrel Cannon. Collecting them all will make the Puzzle Piece appear.

Enemies

 * Tucks
 * Tuff Tucks
 * Pointy Tucks
 * Painguin Tucks
 * Cheesy Chesters
 * Hootzes
 * Hot Hootzes
 * Blue Hootzes
 * Fluffs