Damp Dungeon

Damp Dungeon is the fourth and an optional level in the Ruins area of Donkey Kong Country Returns. A Map Key is required to access Damp Dungeon after finishing Button Bash, otherwise Donkey Kong can instead go to Mast Blast. After finishing Damp Dungeon or Mast Blast, the level Itty Bitty Biters is made available.

Summary
Donkey Kong and Diddy Kong will enter the Damp Dungeon to find various water mills running off of waterfalls in the cave. The main gimmick of the level is the watermills being used to transverse large gaps, with not every mill functioning the same; some mills don't orbit 360 degrees, while others may be missing platforms or have enemies on them. Enemies encountered include Rawk, Stilts, Tiki Torches, and finally, Snaggles where there is water.

This level isn't particularly notable for difficulty, however it is notable for the secrets and hidden areas -- having a total of nine collectible Puzzle Pieces means that Donkey and Diddy will have to check every nook and cranny to find them all. In addition, there are two Bonus Rooms to be found, and over a dozen Banana Coins to be found.

Enemies

 * Rawk
 * Screaming Pillar
 * Snaggles
 * Stilts
 * Tiki Torch

Items

 * Banana Coin: 16
 * DK Barrel: 2
 * Heart: 4
 * Extra Life Balloon: 2
 * K-O-N-G Letters:
 * K: On a broken platform below a grassy ceiling.
 * O: In the center of a watermill.
 * N: Hovering near a barrel cannon. Simply ride the water mill up to get at a viable position to jump and obtain the "N".
 * G: Hovering above a Stilts. Also directly above the bonus room entrance.
 * Puzzle Pieces:
 * 1: Inside a bag hanging from the ceiling. A DK Barrel can be held and brought to the proper spot to be thrown at the bag and reveal the piece.
 * 2: Ground pound a leafy floor to find the second piece.
 * 3: Inside a vase.
 * 4: Ground Pound a Screaming Pillar after it falls.
 * 5: Below a fast spinning watermill, blow a dandelion.
 * 6: After the checkpoint, go to the lower platform, jump to the grassy ceiling, and climb to the bonus room to earn the sixth piece.
 * 7: Blow a windmill underneath a barrel cannon.
 * 8: Inside a bag hanging from a ceiling -- similar to the first puzzle piece, keep a barrel handy and toss it at the bag.
 * 9: Obtained by completing the bonus room.

Bonus Levels

 * Donkey and Diddy Kong will have thirty seconds to collect three Banana Coins and 99 Banana Coins that orbited above a bouncy, moving platform.
 * The Kongs have thirty seconds to accumulate an Extra Life Balloon, three Banana Coins, and sixty Bananas. This bonus room is arranged with four barrel cannons placed north, south, east, and west. The items are found by blasting in between them.