After proving himself in two separate timelines during Dragon Ball Z, Dragon Ball GT makes it official that Trunks is the greatest all-around fighter.
The first time fans were introduced to Trunks, he was actually an alternate version of a character who hadn’t even been introduced yet. Trunks is the son of Vegeta and Bulma, but that wasn’t immediately obvious upon his debut. Fans met a Trunks from an alternate future who traveled back in time to warn the Z-Fighters of the impending threat of the Androids, and then again to train with them to stop the Androids and Cell before they wrecked this timeline just as they did his. During the Android Saga, Bulma gave birth to the Trunks of the prime DBZ timeline–though it wasn’t until well after the Cell Saga that fans got to see this version of Trunks in action. Even as a little kid, Trunks showed immense power and fighting ability, so much so that he and Goten were recruited to battle Majin Buu when no one else was strong enough to. Future Trunks was strong to be sure, but the main timeline Trunks showed promise beyond anyone’s expectations–and he only became more impressive in GT.
In Dragon Ball GT season 1, episode 5 (written by Masashi Kubota, directed by Osamu Kasai, produced by Toei Animation), Goku, Pan, and Trunks are traveling the universe, searching for the Black Star Dragon Balls when they find themselves stranded on a world run by a cruel dictator. The Dragon Ball heroes crash-landed on this world because a little piece of the spaceship that was accidentally kicked loose by Pan fell off upon takeoff. Evidently, that piece ended up being instrumental to the overall function of the spacecraft, so after some time without it, the whole ship stopped working and sent the team plummeting down towards the nearest planet. However, by the end of this episode, Trunks has gathered all the parts he needed, replaced the missing piece with a comparable one he found on this alien planet, and essentially rebuilt the ship perfectly.
Trunks is as Strong as Vegeta, & as Smart as Bulma
Trunks’ history in Dragon Ball Z (both Future Trunks and Kid Trunks) showed how strong Trunks was many times–from his debut which depicted Trunks brutally murdering Frieza like it was nothing, to the final chapters of Dragon Ball Z when he fused with Goten and made going Super Saiyan 3 look easy. What DBZ didn’t explicitly focus on, however, was Trunks’ intelligence. Sure, he had to be smart enough to operate the time machine, and his critical thinking during battle helped ensure victory over his opponents (most notably against the future Androids and Future Imperfect Cell), but he was never shown to be on his mother’s level. Bulma is a genius, perhaps the greatest inventive mind on the planet in the world of Dragon Ball, and this episode of Dragon Ball GT proves that Trunks is just as intelligent.
Trunks rebuilt a spaceship designed by Bulma without all the original parts and while on an alien planet with little to no resources at his disposal. This feat is incredibly impressive, and it confirms that Trunks has his mother’s intelligence just as DBZ confirmed multiple times that Trunks had his father’s strength. Vegeta is one of the strongest fighters in the universe while Bulma is easily the smartest person in the world, and Trunks rivals both of them in their respective fields of expertise–so it is all but confirmed that Trunks is Dragon Ball’s greatest all-around fighter, and this one episode of Dragon Ball GT proves it.