Catfish is the ninth level in Castle Crashers. This level is the continuation of Rapids Ride and is the only level in the game that doesn't change into its own scenario. At the world map, the Catfish level can be accessed as a separate level from Rapids Ride.
Being that this level takes place while traversing the river's rapids, the player's movement will be considerably slowed down, so he must procure himself with a flotation device to be able to move through the waters at normal speed. One of these devices will appear each time the player has been knocked down into the water.
The environment consists of a river running through the woods, and which leads to the Bears' village. A giant mutant catfish lurk these waters and the bears seem to have proclaimed this creature as a deity or a pet. Once they discover an intruder has entered their domains, the Catfish will be summoned to attack. The monster will emerge from underwater, ridden by a bear, to confront the player.
Something that makes this level unique is the sudden intervention of the King's boat, which will aid the player against this monstrosity, and which makes its introduction by killing the last Big Fish in the river. The King himself will be commanding the boat, and three Gray Knights will also be on board. A giant cannon, installed on top of the boat, will be managed by one of these knights. The boat can withstand the powerful blows of the Catfish, and the player is expected to lead the monster so the boat can shoot a cannonball to stun it.
Once the Catfish has been defeated, the corpse of the bear will come afloat and be drifted away by the current.
- Just before the Catfish makes its appearance, a large sack containing fishes to feed the Catfish can be seen on the river bank.
- While Catfish coughs up a hairball, a Gray Knight can be seen loading a cannonball; if the hairball isn't destroyed, the cannonball will fall out into the river. This can be difficult to notice if it's your first time fighting it.
- When Catfish rams into the boat with its charge attack, it can take damage from weapon enchantments (ex: Demon Sword's fire).
- If the boss is not lined up horizontally with the ship, the cannonball will miss or fail to stun the Catfish.
- The music that plays throughout this level (beginning after the bubbles appear) is Child of the Corn by The Behemoth. The track is named for the Corn Boss, as it plays during that fight as well.