The general of the Machine Mutant army and second in command after Dr. Myuu, General Rilldo is the first real opponent that Goku goes up against in Dragonball GT. General Rilldo is certainly a nuisance with his various android-like abilities such as absorbing pieces from the Sigma Force and his various rocket punches and energy attacks. However, Rilldo’s ability to turn anything he wishes into metal soon becomes a serious situation when Goku, Pan, and Trunks all fall victim to this attack. However, General Rilldo’s true power lie within his transformations, especially when he reveals his connection to the entire planet of M2 itself. It is because of these transformations that we see Goku transform into Super Saiyan 3 for the first time in GT, confirming how strong of an opponent Rilldo really is.

The resulting fusion between Uub and Fat Buu, Majin Buu first appears in GT as the only fighter left to go against Super Baby Vegeta 2 due to every one of the Z fighters falling to Baby’s mind control and Goku getting his tail regrown on the Kai planet. Majin Buu is essentially Uub with a major power upgrade and Fat Buu’s signature ability to turn anything into candy, and his strength is best evidenced through his fight with Super Baby Vegeta 2 and his killing of General Rilldo during the Super Android 17 Saga. Majin Buu also shows in the fights with both Super Android 17 and Omega Shenron that he can last somewhat longer against them than Trunks, Goten, and Gohan due to the strength from his fusion as well as his variety of energy attacks, with the Chocolate Kamehameha being his signature. Although we never get to see him go the distance with any opponent, Majin Buu certainly proves that he’s among the A team for the Z warriors.

The twin brother of Nova Shenron, Eis is the Shadow Dragon connected to the 3 Star Dragon Ball, and was created by the wish to erase everyone’s memories of Majin Buu on Earth save the Z warriors and friends. Like Nova’s abilities with fire, Eis uses ice based attacks in his fight with Goku, where his most effective techniques are freezing Goku’s appendages and actually blinding him. Unlike Nova, however, Eis has no sense of honor, using dirty tricks and doing whatever it takes to win no matter what; even Nova turns against him due to these tactics. Despite this, however, Eis possesses the strength to actually force Goku to go Super Saiyan 4 out of necessity, being one of the few villains in GT to do so.

The twin brother of Eis Shenron, Nova Shenron is the Shadow Dragon connected to the 4 Star Dragon Ball, and was created by King Piccolo’s wish to restore his youth way back in the middle of Dragonball. Nova’s abilities revolve around the use of fire based techniques as well as the power to generate heat even hotter than the Sun. As in his battle with Eis, Goku is forced to transform into Super Saiyan 4 out of necessity in order to actually stand a chance of beating Nova, placing him among the few villains that Goku does this for. Nova ranks firmly as the second strongest Shadow Dragon based on his battles with both his twin brother as well as Omega.

A fusion of Android 17 and the Hell Fighter 17 built by Dr. Gero and Dr. Myuu in Hell, Super Android 17 is one of the strongest villains the Z fighters face off against in GT. Super Android 17 is deadly in the sense that he has a variety of offensive and defensive energy techniques for both close combat as well as ranged combat. His most critical ability, however, is his absorption barrier, capable of absorbing even the strongest of energy attacks directly through his chest. As a result, Super Android 17 makes short of work of almost all the Z fighters, with only Majin Buu and Vegeta really giving him some sort of a matchup until he absorbs their energy attacks to get stronger. Not even a 10x Kamehameha from Goku in his Super Saiyan 4 form stops him. It takes a combination of Android 18 appealing to the original 17 to expose a weak spot and Goku utilizing his Dragon Fist technique to finally defeat him. Although his reign was short-lived, Super Android 17 certainly caused a legitimate amount of mayhem before he was defeated.

The last of the Tuffles, a race exterminated by the Saiyans who then made the Tuffle planet their new home, Baby is the first main antagonist in GT. Brought back to normal by his creation, Dr. Myuu, Baby himself isn’t as physically strong in comparison to many of the other fighters in the series. What marks him as a serious threat, however, is his ability to possess anyone’s body. While Baby does this several times on his journey to Earth to exact his revenge on the Saiyans, it is his possession of Vegeta that marks him as a legitimate villain, leading to the control of almost everyone on the entire planet as well as utilizing Vegeta’s abilities in remarkable ways, such as creating his Revenge Death Ball. It is also his transformation into Golden Great Ape Baby that marks him as the 2nd strongest villain in the series. Definitely a threat to say the least.

Even though Vegeta is more or less retired when we first see him in GT (the mustache pretty much confirms his new role so to speak), that doesn’t mean the prince of all Saiyans has let up in training by any means. This is best confirmed by what Baby puts him through in his hostile takeover of Earth as well as the new technique that he uses in his fight with Super Android 17. It may only be through the use of focused Blutz Rays via Bulma’s invention in DBGT that he’s even able to transform into Super Saiyan 4 in the fight against Omega Shenron, but despite how he got there, it puts Vegeta at a plateau that few can match, and therefore marks him as one of the strongest characters in GT.

The final Shadow Dragon and the final opponent the Z fighters face in GT, Omega Shenron was created by Mr. Popo’s wish to revive everyone on planet Namek killed by Frieza and his men. Omega Shenron is the result of Syn Shenron absorbing all 7 of the Dark Star Dragonballs, resulting in strength beyond imagination and a vast array of energy techniques. Not only is Omega able to go up against Gohan, Goten, Trunks, Pan, and Majin Buu all at once, he also takes on Super Saiyan 4 Goku and Super Saiyan 4 Vegeta at the same time, and even goes head to head with Super Saiyan 4 Gogeta. Omega Shenron is only defeated in the end by Goku creating the Universal Spirit Bomb, which was made up of energy collected from all beings across the galaxy in order to destroy him once and for all. Omega Shenron is the strongest villain in GT without question.

The main character of Dragonball GT, Goku’s intro to the series is certainly unique as he’s turned into a kid due to Emperor Pilaf’s mistake after successfully using the Dark Star Dragonballs. Despite this setback, however, Goku still proves that he packs a punch as he’s able to transform into Super Saiyan 3 during his travels across the universe with Pan and Trunks in order to gather the Dark Star Dragonballs together. Just like in Dragonball Z, Goku takes it to the next level through his transformation into Super Saiyan 4. Because of this new level, defeating the likes of Baby, Super Android 17, and Omega Shenron, and his use of techniques such as the 10x Kamehameha, Dragon Fist, and the Ultimate Spirit Bomb, Goku is easily the strongest individual character in GT, and deservedly so.

He’s only around for 10 minutes due to Goku’s exhaustion from fighting Omega Shenron before Vegeta’s arrival, and spends a good amount of it boasting and toying around with the Z fighter’s strongest opponent ever. Yet both of these facts actually help mark Super Saiyan 4 Gogeta as the strongest character in Dragonball GT. The result of Goku and Vegeta performing the Fusion Dance as a last ditch effort to stop Omega Shenron, Super Saiyan 4 Gogeta completely delivers on the promise of immense power. Omega Shenron’s attacks have absolutely no effect on Gogeta, which is best seen by Gogeta effortlessly kicking away Omega’s strongest energy attack. In response, Gogeta’s Big Bang Kamehameha completely obliterates Omega’s form back down to Syn Shenron’s original form before absorbing the Dark Star Dragonballs. Gogeta may toy around with Omega to the point where he talks up a big attack only to reveal party poppers as a joke, but Gogeta is able to achieve a plateau unmatched by any other fighter in GT. That alone is what marks him as the strongest character in GT.