The chief villain in the Donkey Kong Country series of video games. K. Rool is the leader of the Kremlings, a race of crocodile-type creatures that walk upright. K. Rool (as in "cruel") is the fattest, meanest, greediest Kremling of them all.

In Donkey Kong Country he took the role of king and waiting on his ship for Donkey Kong and Diddy Kong to come try and take back the banana horde that he had stolen. He utilized a charging attack as well as throwing his spiky crown at the apes, plus he arranged for cannonballs to rain down upon them.

After being defeated he returned in Donkey Kong Country 2: Diddy's Kong Quest and took on the title of Kaptain K. Rool and became a pirate. He kidnapped Donkey Kong and, in typical pirate fashion, held him for ransom. During the final encounter the kaptain shoots cannonballs that Diddy Kong and Dixie Kong must pick up and toss into the kaptain's gun, causing it to explode.

Donkey Kong Country 3: Dixie's Double Trouble saw K. Rool becoming a mad scientist. As Baron Von K. Rool, the Kremling leader dispatched a variety of mechanical enemies to stop Dixie Kong and Kiddy Kong. In the end he was defeated when the two apes tossed barrels at his propeller-pack, causing him to fly out of control.

By the time Donkey Kong 64 rolled around K. Rool had returned to being a king and had taken by boxing. The final boss battle featured the king trying to pulverize the Kong klan with various boxing moves.

The three Game Boy Donkey Kong Land games (DKL, DKL2, and DKL3) featured K. Rool in his former roles of king, kaptain, and mad scientist once again and utilized similar attacks as outlined above.

It is unknown if K. Rool will return again seeing as how he is a Rareware creation which is now owned by Microsoft. However Nintendo does retain the Donkey Kong character license, so time will tell if he reappears in a future Donkey Kong game.