The boxing arena is a large area inside the King Kruiser II in Donkey Kong 64. It is where the five Kongs engage in a final boss battle against King Krusha K. Rool. The boxing arena is the same size as a normal boxing ring, despite it being much larger than the King Kruiser II.
The boxing arena ring is in the shape of a square, and it is located in the center of the area. Each side of the arena has the message "K.Rool's the King!", accompanied by the Nintendo 64 logo on the left and the Rare logo on the right. The rope dividers are white in the center and a unique color for each corner: red, blue, yellow, and green. The floor of the ring has four red star designs, each near a corner, and four smaller stars appear in front of each four rope dividers. Like Battle Arena Pads, there is a faint mugshot of K. Rool's head in the center.
The boxing arena is symmetrical. There are large light fixtures hanging above the ring, and in the background there is a single floor of bleachers and large stadium lights above them. The floor outside the ring is stone gray, and there are two open entrances, which appear left and right of the boxing ring each. The casing around the entrance is shaped like a pentagon, with white lights illuminating from it. From both entrances there are three pairs of lights on the floor, and they lead in the direction to the boxing ring.
Located between two of the large stadium lights is a press box, where the two Kritters ring the bell during the matches. The bell is rung from one of two red buttons, each from one of the Kremlings. The Krem Co. clock (which previously appears in Frantic Factory) appears behind the Kritters. Both of them use a large crate as a seat.
After the Kongs deactivate the Blast-o-Matic, K. Rool attempts to flee in his airship, the King Kruiser II. K. Lumsy chases it around and accidentally trips over a rock. He swings his arm and accidentally knocks the airship down onto the shore of DK Isles. A hole breaks open on top of the King Kruiser II, where the Kongs can jump into to enter the boxing arena.
In the boxing arena, the ring announcer introduces the match to the audience and describes it as "twelve 3-minute rounds of boxing for the undisputed heavyweight championship of DK Isles". He then mentions the sponsors, Rare and Nintendo in associated with "K. Rool Enterprises". He introduces the contestants: the Kong Family (Donkey Kong, Diddy Kong, Lanky Kong, Tiny Kong, and Chunky Kong) against King Krusha K. Rool. During his introduction, King Krusha K. Rool appears from the ceiling, holding on a rope and waving to the audience. As the ring announcer bounces away, K. Rool lands into the ring and accidentally squishes the ring announcer, who squirms away. The ring announcer finally states that there are no judges and that the timekeepers are fair and unbiased. From the press box, a Kritter hits a red button to ring the bell, and the battle begins.
After K. Rool loses to each of the five Kongs, the Kritters try to make him get up. As Chunky is celebrating his victory, K. Rool's opens his bloodshot eye and charges at Chunky. Right before he hits Chunky, K. Rool hears a whistle. He looks to the left of the arena and sees Candy Kong walking in. She distracts K. Rool by acting flirtatious to him, causing K. Rool to feel love struck. He forgets about Chunky and leans against the rope dividers, attempting to reach for her. Meanwhile, Funky Kong enters from the right of the arena. He is carrying a wooden launcher with a red boot attached to it, and Funky launches it at K. Rool's backside. Just when K. Rool turns around to look, he gets hit by the boot, which launches him directly up outside the boxing arena, thus defeating him.
During the battle, King Krusha K. Rool fights one of the five Kongs in each round. K. Rool's attacks and the events are different per each round. The Kongs cannot attack K. Rool with their basic moves, which are ineffective against him, as it results it them losing health. They cannot use their personal weapon or instrument during the battle. Each must use a specific method of attacking K. Rool four times to knock him down for the round. Each round lasts 2 minutes and 30 seconds (despite the ring announcer saying that each is three minutes), and a countdown timer appears on the bottom of the screen to keep track of the time. It takes a minimum of five rounds to defeat K. Rool, one per each Kong. When K. Rool gets knocked down, this ends a round, and the countdown to ten starts. With the first four Kongs, the two Kritters in the press box always hit the bell before the countdown reaches ten; when the countdown stops, an announcer says, "saved by the bell".
If the Kongs fail to defeat K. Rool within twelve rounds or by losing all their health, they must restart the battle. The first time when the Kongs are unsuccessful at knocking down K. Rool within the time limit, a scene shows Cranky Kong coaching the Kong at a corner of the arena. He demonstrates some fighting moves to the Kong, only to hurt his back. If the same Kong participates in the next round, they retain their health. Every Kong starts out with full health, regardless of the previous one's status.
Donkey Kong is the first Kong to fight against King Krusha K. Rool. During the round, K. Rool remains in the center of the arena. He attacks by jumping then pounding onto the ground, which generates a green shockwave which moves across the ring. Donkey Kong can avoid the shockwave by either jumping over it or climbing onto one of the arena's four posts. After K. Rool generates a shockwave three times, four Barrel Cannons appear above each post, each pointing at K. Rool. Donkey Kong must jump inside one, and the perspective changes to inside the Barrel Cannon. K. Rool throws a few punches, prepared to hit Donkey Kong when he blasts out. However, after throwing a few jabs, K. Rool gets distracted by the audience's applause, which he happily takes in, though after a few seconds, K. Rool returns to throwing jabs. Right when K. Rool is distracted, Donkey Kong must blast into him. When he blasts out, the screen perspective goes back to normal. Upon being hit, K. Rool gets knocked back slightly. This phase occurs three more times.
For each hit, K. Rool responds more quickly. After K. Rool takes a hit, the lapse between his ground pounds are shortened. After taking a second or third hit, K. Rool generates four shockwaves each time he pounds onto the ground. After each hit, K. Rool throws a different number of punches before shifting his attention to the audience: after one hit, K. Rool throws five punches, after a second hit, he throws three punches, and after a third hit, he throws seven punches.
When K. Rool is hit a fourth time, he is hit in the face and falls down. The countdown to ten starts, and the scene switches to two Kritters in the press box. They sit around until the countdown goes to 8, when the Kritter on the right suddenly gets up and punches the button repeatedly and rapidly. He then sits back down while the other one stares at him.
Diddy Kong is the second Kong up against King Krusha K. Rool. At the start of the battle, K. Rool waves at the audience. He stands in the corner of the red-colored ropes, where he repeatedly attacks by throwing one of his large boxing gloves like a boomerang at Diddy. If a boxing glove hits Diddy, he loses a quarter of a melon in health. After doing this twice, a Diddy Barrel appears in the center of the ring. Diddy must jump inside the barrel to perform Rocketbarrel Boost (which runs on indefinite Crystal Coconuts and shoots indefinite ammo during the battle) and then ascend to the large lighting fixtures. Throughout the round, K. Rool continues throwing his large boxing glove in the direction of Diddy.
To attack K. Rool, Diddy must shoot twice at two red targets, each on an opposite side of the light fixture. By doing so, the light collapses onto K. Rool's head and gets stuck. K. Rool walks to the next corner of the ring, pulls the light off him, and throws it aside. The cycle is repeated three more times, and the boxing arena gets darker with each light fixture that falls. When the fourth light fixture crashes on K. Rool's head, it remains stuck and he collapses. As a result, the whole ring becomes dark due to a lack of lighting. The countdown begins, during which another scene of the two Kritters in the press box is shown. They are sleeping on the floor, though upon hearing the countdown, the Kritters wake up and return onto their seats. The Kritter on the left hits the bell right when the countdown reaches 8.
Lanky Kong is the third Kong to fight K. Rool, whose head is still stuck in a light fixture. Since K. Rool cannot see, he runs forward in random directions, attempting to run onto Lanky (always in a pattern from red to blue to yellow, then from red to green to blue, and lastly from yellow to green to red). After ten seconds, four boxes appear around each side of the arena. Each box has a switch with its own number (1, 2, 3, and 4) and color (green, blue, yellow, and red respectively). By hitting one of the switches, a small platform rises up with a barrel containing a large banana peel. This causes a Music Pad to appear in each corner of the arena. Lanky must quickly take the barrel off the platform, which returns back into the ground after five seconds. Lanky must throw the barrel near the center of the ring to release a large banana peel. When the banana peel is centered between Lanky and K. Rool, he must perform Trombone Tremor. Right after Lanky plays it, K. Rool runs in the direction of the sound, only to trip on the large banana peel. If Lanky does not align the banana peel properly, K. Rool charges straight into Lanky, who loses a quarter melon of health. When Lanky starts performing on the Music Pad, the numbered platform that he activated retreats into the ground. Like the previous rounds, the cycle repeats three more times. After slipping on a fourth banana peel, K. Rool falls backward and the countdown starts.
A third scene of the two Kritters are shown, the Kritter on the right hits the bell when it reaches four, but is unsuccessful at stopping the countdown. The Kritter then hits each red button a few more times, and the countdown ends at eight once again. Even when the countdown stops, the Kritter begins to jump on each button which activates the bell. The other Kritter covers its face in annoyance, and the Kritter continues jumping on the bell until the view zooms out of the press box.
Another scene plays, where the Kritters are attempting to pull the light off K. Rool. One Kritter is directing the other one to pull it off: two Kritters are pulling from the front, one Kritter is sitting on top of the light on K. Rool's head, one Kritter is pushing from behind, and another Kritter is pulling K. Rool's tail. The Kritters manage to pull it off, though all of them get squished by K. Rool. The ones in the back are squished by K. Rool's behind while the ones in front are squished by the lighting fixture. K. Rool goes back into the ring. Starting the next round, all four lighting fixtures return above the ring.
Tiny Kong is the fourth character to fight K. Rool. Similar to latter part of Donkey Kong's section of the battle, K. Rool attacks by slamming onto the ground, generating four shockwaves. Instead of staying in the center, K. Rool moves between corners of the arena. After performing two ground pounds, K. Rool hurts his behind. He briefly stops to take in the applause from the audience. K. Rool then performs two more ground pounds. K. Rool hurts his behind and briefly stops fighting. During this, a Tiny Barrel appears for Tiny to perform her Mini-Monkey ability (which has unlimited fuel for the battle). She must walk into the hole of K. Rool's left shoe. The round timer pauses while she is inside the shoe. In the shoe, Tiny carries out her Feather Bow (which, like Diddy's popguns, has unlimited ammo during the battle). K. Rool wiggles one or two of his toes forward then back a couple of times. When K. Rool lifts up a toe, Tiny must shoot a feather at it (this also causes a high-pitched laughter-like sound effect to play). Tiny runs out the shoe, and K. Rool hops while holding up his left foot in pain, then falls backward. The fight resumes, and like the rounds with the previous three Kongs, the cycle repeats itself three more times.
Upon each hit K. Rool takes, he moves around the ring faster and performs one more ground pound than he previously did (after one hit, K. Rool ground pounds three times, after two hits, he ground pounds four times, and after three hits, he ground pounds five times). During when K. Rool's behind is hurt, Tiny is given less time to enter into his left shoe under her Mini-Monkey ability. Each of K. Rool's toes become more sore each time he is hit. After wiggling his toes a bit, K. Rool lifts up the next toe. For each hit K. Rool takes, the cycle of Tiny avoiding K. Rool's wiggling toes and then shooting at one of his lifted toes repeats another time. Once all four of K. Rool's toes are injured, K. Rool falls over backward and faints. The countdown starts, and a final scene shows the two Kritters in the press box. As the numbers count down, the two Kritters look at each other, anticipating when the other will hit the bell. When the countdown reaches 7, each Kritter slam both their fists on their respective red button, causing the bell to launch off the contraption and land in front of it right when the countdown reaches 8, where it stops at a fourth time.
Chunky Kong is the fifth and final Kong up against K. Rool. Just before the round starts, the left Kritter in the press box instinctively hits the red button, even though its corresponding bell fell off earlier. The other Kritter is holding the bell and instead rings it by hitting with his fist.
During Chunky's part of the round, K. Rool repeatedly goes to a side of the ring, pulls back from the center of the dividers, and then runs to the next side, repeating the process. K. Rool turns invisible during the battle, and his current position can only be identified from his shadow on the ground. A few seconds after the battle starts, a blue Chunky Switch appears in the center of the ring. Chunky must Simian Slam onto the switch to make a Chunky Pad appear on each side of the ring. Chunky must stand on any pad to activate his Gorilla Gone ability. This causes a Chunky Barrel to appear above the center of the ring. K. Rool is visible whenever Chunky is under the effects of Gorilla Gone. By jumping into the Chunky Barrel, Chunky can activate his Hunky Chunky ability.
Right when Chunky activates the Hunky Chunky ability, he and K. Rool stand on opposite sides of the arena, the red corner and blue corner respectively. K. Rool then charges at Chunky, who must time his Primate Punch by using it on K. Rool shortly before he runs into Chunky. If Chunky correctly times his Primate Punch, K. Rool stops and skids in front of Chunky, who briefly prepares a punching attack before unleashing it on K. Rool, who gets hit all the way to the other side of the arena. If he fails to attack K. Rool, Chunky gets hit by an uppercut attack from K. Rool.
After Chunky Kong performs from a Chunky Pad, one of them disappears. The Chunky Pads always vanish in a specific order, regardless of which order Chunky uses them. They always disappear in order from: the green corner, then blue, then yellow, and lastly red. For each hit K. Rool takes, he moves around the boxing arena even faster. Before K. Rool takes his final hit from Chunky while under his Hunky Chunky, K. Rool moves around in a slower, zigzag pattern while invisible.
Like the previous rounds, K. Rool must be hit four times to be knocked down, though this time, K. Rool loses entirely. Altogether, K. Rool is defeated from taking 20 hits. Upon taking a final hit, K. Rool lands on his knees and then hits his face onto the ground. This battle ends with Chunky celebrating his victory while a few Kritters try to get K. Rool back up to continue fighting Chunky.