|“||Sniff... K. Rool says I'm too soft to be a Kremling and I'm to stay in here until I've toughened up.||„|
|~ K. Lumsy|
He was imprisoned because he didn't want to smash the Donkey Kong Island during the Kremling invasion. His jail was locked with eight locks, and seven of the keys were hold by elite soldiers. The jail is inside a cave who is tied to Crocodile Island. So it is released, he helps Kongs against K. Rool.
When K. Lumsy is ordered by his older brother King K. Rool to smash Donkey Kong Island during the Kremling invasion, he refuses. This act of disobedience results in K. Lumsy being imprisoned in a large cage with eight locks. The keys to these locks are given to various minions of the Kremling king, who are commanded to protect the keys at any cost. The cage itself is tethered to Crocodile Isle, the moving base of operations of the Kremling Krew. K. Lumsy is to remain in the cage as punishment for his actions and is only to be released when he learns to be a vicious destroyer who has no sympathies towards the Kong Family.
Fortunately, Donkey Kong stumbles upon K. Lumsy’s prison and learns of his plight. Ever the hero, DK promises to free the innocent Kremling from his cage. This in turn causes K. Lumsy to jump and dance for joy, causing small tremors across the island that open Jungle Japes, the lair of Army Dillo, guardian of the first key needed to unlock the cage.
Donkey Kong eventually defeats Army Dillo and recovers the first key. After opening another lock on K. Lumsy’s cage, the massive Kremling once again jumps for joy, and once again, another area is opened as a result, allowing the Kongs to recover more keys (not to mention rescue other allies and collect the stolen Golden Bananas).
Once all eight keys are recovered and the last lock on his cage is removed, K. Lumsy finally achieves his long awaited freedom. Immediately after exiting his cell, K. Lumsy notices an airship flying through the sky. K. Lumsy chases after the plane as if it were a child’s toy. As it turns out, this airship is the King Kruiser II, K. Rool’s personal means of escape from Donkey Kong Island after the Kongs foil his plan to destroy it. K. Lumsy trips on a rock while chasing the airship and accidentally knocks it out of the sky. It crashes onto the shore, and the Kongs then enter it and engage K. Rool in a final showdown.
After K. Rool's defeat, he is sent flying through the air by Funky Kong, crash landing on K. Lumsy's Island before being beaten by the giant crocodile and sent flying through the roof. In the ending, the giant Kremling later gives the Kongs a ride around the waters of Donkey Kong Island.