Dragon Ball's Buu looks like something of a joke character; he’s pink, he’s pudgy, and, more often than not, he doesn’t know what the hell he is doing. However, Dragon Ball Z leaned into the danger of a super-powerful being without much of a conscience or a moral compass. Throw in his ability to absorb people and change forms, and Buu becomes particularly meddlesome.
Towards the end of the show, Buu had many transformations and even a reincarnation. Additionally, the adventures of both Buu and the reincarnated Uub continued on the divisive Dragon Ball GT show. Accordingly, fans have spent years trying to determine which versions of Buu are the strongest.
Updated on July 22nd, 2022 by Tanner Fox: From a being hellbent on the total destruction of Earth to a mild-mannered humanoid under the tutelage of Goku, Majin Buu has undergone quite a few transformations and reincarnations throughout the Dragon Ball saga. Sometimes a goofy mass of pink flesh and sometimes an ultra-muscular menace, Buu's forms vary so significantly that they could be counted as completely separate characters.
Buu is best remembered as a power-hungry rival of Goku, but that's not always the case. Some of his incarnations don't possess much power at all.
Mr. Buu
Mr. Buu has to be the weakest version of Buu; his essence has been torn from that of Innocent Buu. Thus, he’s lost the cohesive power of his whole self and been split into two aspects—a good side and an evil side. With that in mind, as eloquently put by Spaceballs' Dark Helmet, “evil will always triumph because good is dumb.”
This version of Buu is the “good” part of Innocent Buu, meaning that he doesn’t have the killer instinct that many of the other forms do. He also has few powers relative to the others, as he is not able to absorb energy through his body as he once did, nor can he power up as easily. This guy still has a lot of raw power—he is still Buu, after all—but, compared to his other versions, he’s pretty meek.
Innocent Buu
Innocent Buu may sound like a less-than-intimidating name, but the term “innocent” is relative; this version of Buu still has extraordinary powers, and he wasn’t afraid to use them to destroy things—and people—that got in his way. In fact, he’d sometimes destroy things just for fun.
Buu effectively lacked a moral compass; he wasn’t afraid to engage in crimes all the way up to mass murder, and he actually took great pleasure in the horrific actions that he performed. He initially lacked the capacity to understand that the pain and death he brought were actually bad things, and, once the Grand Supreme Kai aspect told him, he was willing to change his ways.
Fat Buu
As the name implies, Fat Buu doesn’t look like a very huge threat to anyone. However, looks can be deceiving, and this Buu has some of the same extraordinary absorption powers of his other forms—and that's saying something, as, in his previous form, he’d managed to absorb the South Supreme Kai. Afterward, he was transformed into Fat Buu by the Dai Kaioshin.
In this form, Buu is something of a mixed bag. On one hand, he has a lot of raw power. Yet, the Kai seemed to have a tempering influence on Buu’s raw power. as he has previously been sealed away by Bibidi, and Goku has the power to defeat him. Plus, his main weapon is a chocolate beam, and, while many fans would kill for a real-life version of that move, it’s just not very intimidating.
Evil Buu
Unlike some of these goofier transformation names, “Evil Buu" sounds like the name of a villain not to be trifled with. Evil Buu is the opposite of Mr. Buu and represents the dark side of Buu’s personality, and this collection of dark energy makes Evil Buu a very dangerous customer, indeed.
He’s certainly got the supervillain appearance down with his gray skin, low voice, and dramatic purple cape. He’s also got the killer instinct; one of the first things he does is to murder Van Zant as a punishment for shooting Buu’s friend, Mr. Satan. He also kicks the good Buu’s butt, and, after the good Buu becomes chocolate thanks to a reflected chocolate beam, Evil Buu proceeds to eat him.
Super Buu
As it turns out, Evil Buu eating the chocolate Good Buu had some weird side effects, causing him to turn into Super Buu. As far as Buu transformations go, Super Buu represents a full Six Million Dollar Man-esque makeover. Buu has been remade, and he’s better, stronger, and faster—not to mention smarter!
Super Buu even manages to look physically intimidating. He’s ditched both the “freshman fifteen” and “supervillain” looks for a sleek, muscular build worthy of challenging Goku. While he is not as wholly immoral as Evil Buu, he’s extremely dangerous, threatening all life on Earth.
Fusion Buu
By this point in the ongoing Dragon Ball Z story, the act of fusion had become a major storytelling component. Characters could fuse their powers and their entire selves together to create a newer, even stronger being. While this was mostly a trick reserved for the good guys, the world trembled when Buu began doing it.
Buu was being easily beaten by Gohan and realized that he needed a helping hand to achieve victory. In order to do this, he managed to fuse with Gotenks by using his special absorption power. This changed his appearance in some notable ways that ranged from a more human-looking face to him wearing a jacket that resembled Gotenks’ jacket. He didn’t just get the looks, though; Fusion Buu managed to absorb some of Gotenks’ powers, too. He may have stayed in this form indefinitely, but, when Gotenks separated back into two bodies, Fusion Buu lost his powers.
Piccolo Buu
After the fusion with Gotenks wears off, Buu ends up absorbing Piccolo. While many Dragon Ball Z fans make the mistake of dismissing Piccolo as a fighter, the truth is that absorbing him gave Buu a dangerous tactical edge.
Absorbing Piccolo gave Buu an intelligence he had never had before. At first, Buu held both Piccolo and Gotenks inside himself, but, later, he’s whittled down to the jolly green Namekian. With Piccolo’s memories and knowledge, he’s able to psychologically torture Gohan, and he also wields dangerous new tricks like the Special Beam Cannon.
Ultimate Buu
Buu’s “ultimate” form represents his most dangerous fusion yet. While fused with Piccolo, Buu manages to achieve his goal of absorbing Gohan. At this point in the series, Gohan is one of the most powerful fighters on Earth, meaning that Ultimate Buu wields an unprecedented level of power.
As with the other fusions, absorbing Gohan resulted in a change of clothes for Buu. Specifically, he started sporting Gohan’s red uniform. He also sported new abilities that extended beyond a costume change, as his body had increased physiological and psychological defenses to help him deal with Goku and Vegeta when they started fighting back from the inside. While this was the strongest Buu they had faced yet, there are other forms that have more raw power.
South Buu
The so-called “South Buu” represents Buu after he absorbs the South Supreme Kai who was inhabiting Otherworld. Unfortunately, fans don’t see Buu do a lot in this form, so his strength is tough to accurately determine.
The only real data point concerning Souther Buu's power level comes from watching the South Supreme Kai fight. In a quick scene that most Dragon Ball fans dismiss as filler, Kai is able to hold his own in a fight with Kid Buu, which is one of Buu’s strongest forms. At the same time, it is known that Kid Buu was not fighting with his full strength and was likely simply testing the Kai. Thus, the Kai ended up with a relatively strong place on this list, but Kid Buu is still better.
Kid Buu
Kid Buu's sheer recklessness is what gives him an edge over most of his contemporaries. He’s got a ton of power and nothing to really hold him back. He doesn’t care who he kills, and that includes himself.
In terms of lethality, it doesn’t get much more serious than Kid Buu. The destruction of the Earth kills billions of people, including notable heroes like Piccolo and Trunks. Fortunately, Goku and Vegeta are able to work with Dende and other characters to bring everyone back to life with the Dragon Balls. At this point, a Super Saiyan Goku and his Spirit Bomb are enough to destroy Kid Buu. However, this is not the last we see of him.
Uub (Younger)
A very consistent feature of Dragon Ball Z is that Goku has a pure heart. Even as he obliterates Kid Buu to save the world, he wishes that he could challenge a non-evil version of his opponent to a rematch someday, and, because Goku has friends in high places, Otherworld’s own King Yemma makes sure that Buu is reincarnated as Uub.
At first glance, Uub doesn’t look like he’s anything special; he's just a scrawny human male. However, fans are eventually treated to the rematch Goku hoped for when Uub enters the World Martial Arts Tournament. It takes Uub a moment to gather his confidence, but, very soon, he’s holding his own against Goku.
Uub (Teenage)
The controversial Dragon Ball GT gives fans more of Uub’s story. Specifically, he's seen again five years after Goku became his mentor. At this point, Uub is fifteen years old and stronger than ever. After he gives Goku a big enough challenge during training, Goku declares that Uub’s training is complete. While Goku had held back during their first fight at the World Martial Arts Tournament, Goku now thinks Uub is ready.
Of course, the overarching message of Dragon Ball is that there is always a tougher opponent around the corner. Uub discovers how true this is when he squares off against an alien opponent named Baby. Baby is the real deal, using psychic powers to control almost everyone on Earth, including Uub’s allies Videl and Gohan. Uub is easily beaten by Baby and has to resort to fusion in order to save himself—and potentially the entire planet.
Majuub
After all of the fusing that has characterized the different forms of Buu, it makes sense that things would come full circle and he would fuse with himself. Seeing no other choice, Uub fuses with Majin Buu, who is back as a pure-hearted good guy. By merging together, they become a powerful character named Majuub!
Uub gets the predictable power boost from this fusion. Plus, in the fused form, he has access to Majin Buu’s ability to turn people into candy. While Majuub gets a lot of raw power from Majin Buu, he retains much of the tactical training from Goku. The audience sees this most clearly when he allows himself to be turned into chocolate and eaten by Baby Vegeta. It turns out this is a plot to attack Baby from the inside. This buys Goku enough time to finish Baby off, and Majuub stays in the fused form and undertakes many more years of battling ever-more-powerful foes.