Anyone familiar with the relationship between Dragon Ball’s Goku and Frieza know that they are mortal enemies with only the smallest hint of mutual respect in terms of their respective levels of power, though upon further analysis of Frieza’s greatest defeats throughout his Dragon Ball career, it becomes clear that Goku was never Frieza’s greatest enemy as that honor goes to a completely different Saiyan entirely.
Frieza and Goku first crossed paths during Dragon Ball’s ‘Frieza Saga’ by Akira Toriyama. During that storyline, Frieza and his universe-conquering army travel to Planet Namek in pursuit of the mystical Dragon Balls. Frieza planned to use the Dragon Balls to call forth a wish-granting Dragon and use the Dragon’s magic to become immortal. Though before he was successful, Goku arrived and unlocked his Super Saiyan form for the first time, using the incredible power-up to defeat Frieza and save the universe from his tyrannical rule. However, Frieza was resurrected in Dragon Ball Super continuity, and his grudge against Goku for thwarting his villainous plot has not lessened even after all these years.
In Super Dragon Ball Heroes: Dark Demon Realm Mission! Chapter 2 by Yoshitaka Nagayama, Goku and Trunks (who are known as Xeno Goku and Xeno Trunks) join an interdimensional organization known as the Time Patrol and are immediately sent on a mission through time and space. Evil wish-granting artifacts known as Dark Dragon Balls have been scattered across time, and Xeno Goku and Xeno Trunks have to collect them before the demonic Dark Empire gets its hands on them and uses their magic to conquer the mortal realm. While traveling through the timestream looking for the Dark Dragon Balls, the heroes are able to locate one in the past during Goku’s first battle with Frieza. As Xeno Goku and Xeno Trunks discovered, the Dark Dragon Ball they were after was embedded in Frieza’s chest which granted him immense, dark power which he was using to easily destroy the Goku of the past. However, when Frieza least expected it, Xeno Trunks was able to cut the Dark Dragon Ball out of Frieza’s chest and defeated the villain right then and there.
Trunks defeating Frieza isn’t a new development in the Dragon Ball universe and is actually something that has plagued Frieza throughout his villainous career. After Goku defeated Frieza on Planet Namek, he actually didn’t kill Frieza but instead left him in an incredibly weakened state, drifting through space. Frieza was saved, however, by his father, King Cold, who gave Frieza cybernetic enhancements, making him even stronger than he was before. When Frieza returned to Earth to enact brutal vengeance upon Goku, Future Trunks had traveled from his alternate world and killed Frieza like it was nothing, slicing him in half with his sword before chopping him up into little bits then obliterating those pieces with a strong ki blast. Trunks did what Goku couldn’t do and killed Frieza, just as he did in this chapter of Super Dragon Ball Heroes.Throughout all of Dragon Ball, Goku has killed Frieza once after the villain came back to life in Dragon Ball Super, but Trunks has killed him twice including this victory in Super Dragon Ball Heroes. Plus, Goku has always maintained the mindset that Frieza could be redeemed and hopes to train with him one day so that both of them can grow stronger than they are, whereas Trunks kills Frieza without hesitation or remorse. To kill without guilt, makes him a much colder enemy for Frieza than Goku could ever be.
From the higher number of victories over Frieza than Goku to his absolutely brutal handling of the villain during each battle, Dragon Ball proves Frieza’s worst enemy was never Goku, it is Trunks.
