The Brute Force Federation, also known as their disguised name "Best Fitness Friends", are the main antagonists in the Mario and Luigi RPG 7: Bowser's Inside Story and Bowser Jr.'s Journey side mode, Bowser Jr.'s Journey. Posing as pharmaceutical reps with a cure for the blorbs, they help Fawful infiltrate Bowser's Castle and aim to take out the Koopalings to stop them interfering with their own plans.
Members of this group include Dieter, a thin tie-wearing being who acts as its leader, Kaley, a short drug-addled female being who attacks with sound and flies like a bird, and Beef, a muscular pink individual who provides the group's muscle.
The Brute Force Federation was Beef's idea for their name, however, Kaley wanted the group name to be the Cutie Coalition.
DIETER[]
Dieter is the leader of the Best Fitness Friends and a major antagonist in Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey. He is a tall figure wearing yellow and black clothing with a prominent tie, and takes charge of the group's operations. He uses various German terms, including telling Bowser Jr. "auf wiedersehen" before trying to kill him. This is likely due to "Dieter" being a German name, while in English, it fits in with the food-based theme naming the other Best Fitness Friends have. He is a ranged enemy in battle, and can use the Doppelganger Captain Command.
He is first battled in Bowser Path, where he, Kaley, and Beef take on Bowser Jr., Ludwig, Kamek, and the four Captains from Mario & Luigi: Superstar Saga + Bowser's Minions.
After this, he is next fought alongside both Kaley and Beef in the final battle, where they all take Malatone Formula:X, and after their defeat, merges with them to form the final boss before being defeated for good.
And he is voiced by Matt Charles in the English dub and he will be voiced by Nobuyuki Hiyama in the Japanese dub.
BEEF[]
Beef is a member of the Best Fitness Friends and a major antagonist in the Bowser Jr. portion of the Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey storyline. He is a muscular creature with pink skin, several layers of either muscle or fat, and red hair. He acts as the group's brawn
He is first encountered with the other members of the Best Fitness Friends, and seemingly defeats Ludwig alongside Iggy a bit later on.
However, it is revealed that the situation is not what it seems. Instead, it is revealed that Ludwig had defeated Beef in their encounter, and had been disguising himself as him the entire time. The real Beef was chucked into lava early on, and left in the storage room back at Bowser's Castle afterwards. Presumably, he was freed when Bowser accidentally detonated the Bob-omb storage depot from being immolated as a result of his treadmill experience literally "burning off" fat.
After that though, he returns to the other Best Fitness Friends for their next encounter outside of Bowser's Castle as well as with them in the final battle. Here he merges with Kaley and Dieter to form the final boss, before eventually being defeated for good.
Beef is the only member of the Best Fitness Friends that makes a cameo appearance in the main story, as he is added to the Bob-omb storage room scene, where he appears unconscious.
And he is voiced by Kevin Michael Richardson in the English and he will be voiced by Tetsu Inada in the Japanese dub.
KALEY[]
Kaley is a member of the Best Fitness Friends and a major antagonist in Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey. She is a pink flying creature who attacks using sound based moves with her special skill Discord, which lowers allies' accuracy, and acts as the group's aerial fighter.
Despite acting calm in many cutscenes, it is soon revealed she is quick to temper and has a serious drug addiction, with Ludwig's intel when disguised as Beef suggesting she is highly dependent on the group's supplements.
She is first battled in Dimble Wood, after Ludwig reveals that he has been disguised as Beef for the last hour or so. She is then battled again in Bowser Path alongside Dieter and Beef, before being fought alongside the two of them in the final battle. She then merges with them to form the final boss before eventually being defeated for good.
And she is voiced by Kristen Schaal in the English and she will be voiced by Sanae Kobayashi in the Japanese dub.