The Beagle Boys are enemies that appears in the Country of the Musketeers, where they serve as the henchmen of Captain Pete, the corrupt leader of the musketeers. They can be fought by both Sora, and Riku.
Sora fights the Beagle Boys twice in the story. First on their own, and later alongside Pete. In the second battle, Sora must take care of the Beagle Boys before he battles Pete. They are quite easy to defeat, but can be difficult to stagger with the Keyblade. However, to get around this use Sliding Sidewinder or Spark Dive to knock them down, or abuse one of their status vulnerabilities. Zero Gravity is best recommended, especially when combined with Thundaga to maximize damage. Guarding is heavily beneficial in the fights, but using Counter Rush is not recommended, due to the inconsistency it has in staggering the boys, oftentimes leaving Sora vulnerable to attack when it finishes. By using Zero Graviga and Thundaga often, Sora should have no trouble taking down the boys in either battle. While the Beagle Boys are extremely weak to Zero Gravity, Pete is completely immune to it, so only equip one for the second battle.
Unlike Sora, who battles the Beagle Boys twice in the story, Riku only battles them one time. Additionally, while Sora battles them all at once, Riku instead battles them one at a time. Riku will find the Beagle Boys in various hiding spots, and they will immediately engage him upon being discovered.
The first one discovered will be in the relatively spacious Machine Room, and will start the battle off farther from Riku than the others. As he is a single target, crowd controlling attacks such as Thundaga are not as important for Riku as they are for Sora. While continuing to use Zero Gravity, instead follow up with powerful single target attacks such as Sacrifice, which will deal massive damage at the cost of some of Riku's HP. Unlike Sora, using Counter Aura is safe for Riku to do, as it does not possess a long animation like Counter Rush does and Riku only has a single target to worry about. Using Zero Gravity at appropriate times and following up with powerful commands will quickly put an end to the first Beagle Boy.
The second, while identical in fighting style and AI as the first, can be much harder to properly deal with. He is found in a much tighter, very narrow hallway, and Riku must attack some clothes obscuring the thug to get him to reveal himself. Upon being exposed, the Beagle Boy will instantly begin attacking Riku, so it's best to set up a Balloon trap before engaging him. Avoid using finishers to open up the hiding spot, as Riku can possibly use Block or Dark Barrier to defend himself if he exposes the thug using light attacks. Follow the same strategy as defeating the previous one and this Beagle Boy will go down just as quickly, but be wary of the cramped space.
The final Beagle Boy is fought in a much more spacious area that the other two, allowing Riku to make full use of Flowmotion or safely use strong spells from a distance, such as Dark Firaga, Balloonra, or Triple Plasma. However, he must be revealed in a similar manner to the second. Follow the same strategies as before, and the fight will end extremely quickly. Make sure to clear the area of any Aura Lions, and to clear the floor of the purple mist, as it will make Riku drop quicker. Immediately following the battle, Riku must fight the Holey Moley, so do not have too many commands equipped that are useful for the Beagle Boys, but useless on the giant Dream Eater.