One of the strongest weapons in all of Dragon Ball is the Spirit Bomb, if not the strongest. The Spirit Bomb has been able to kill Kid Buu and nearly every movie villain between Dr. Wheelo and Android 13 as well as critically harm characters like Vegeta and Frieza using spirit energy donated by other lifeforms. Even Goku's eventual unlocking of Ultra Instinct in the Super anime is a result of it.
Given how useful a move it has proven to be over the years, it baffles me that only Goku is capable of using it. Even more unexpected is the fact that Vegeta has never shown an interest in mastering the move. Why hasn't Vegeta yet mastered his rival's most potent move, given that he has dedicated himself to outdoing Goku, and could he do so in the future?
Vegeta Has Committed to Using New Techniques
Some people might find it unexpected that Vegeta learns how to use the Spirit Bomb. Vegeta has always gone to great lengths to contrast Goku, who is most often associated with this move. Though it wouldn't be completely unexpected for the Saiyan Prince to master the technique given recent developments in Dragon Ball Super, it is still possible. After all, Vegeta trained on the planet Yardrat to defeat the long-ago foe in the "Galactic Patrol Prisoner Saga"Subplot," "'s Vegeta's in which Goku and Vegeta fight Moro the Planet Eater. Goku's Instant Transmission move, which enables its user to teleport, was previously credited to Yardrat as its source.
Vegeta's willingness to train on a planet that his archenemy had been to years prior demonstrates that the Saiyan Prince has become more receptive to utilizing Goku's techniques. Vegeta developed his spirit energy on Yardrat to the point where he was able to master the skill known as "Spirit Fission," which involves absorbing or fusing an opponent's misplaced ki to deplete them. Even Goku was unable to learn it, demonstrating Vegeta's aptitude for learning more ethereal techniques and the fact that he no longer relies solely on force to advance. Vegeta is no longer able to get by using only brute force.
Once more, this theme would appear in Dragon Ball Super: Super Hero. The movie demonstrates how Vegeta has diverted his attention to more spiritual endeavors like meditation in order to develop his control over ki to the same level as Jiren's, whereas Goku has grown dependent on sparring with Broly. In the movie, Vegeta defeats Goku using this strategy, demonstrating that the Saiyan Prince's new perspective may finally enable him to outdo his rival.
Vegeta Continues to Insist on Being a Saiyan on His Own
That's all well and good, but does this indicate that Vegeta will soon discover the Spirit Bomb? In some ways, he may have adopted Goku's strategies, but in others, he makes it clear that he has no desire to do so. When Vegeta is eventually forced to use the Instant Transmission on Yardrat to get to Moro in time, he makes it clear that this is a one-time use only. Vegeta never pushes to learn the Instant Transmission on Yardrat.
In the "Granolah the Survivor Saga," Vegeta's desire to set himself apart from his rival reaches a boiling point. Vegeta practices with Beerus to learn the techniques of the God of Destruction while Goku trains with Whis to learn Ultra Instinct. In his battle with Granolah, Vegeta unleashes a new form called "Ultra Ego," which is the result of his training. Ultra Ego gives its user more power the more damage their opponents deal to them, in contrast to Ultra Instinct, which allows its user to move independently to avoid enemies.
It's a form more fitting for the Saiyan Prince, who favors aggression over Goku's more refined methods. Vegeta's recent developments indicate a willingness to embrace a more controlled approach, but at the end of the day, the character serves as Dragon Ball's bruiser in contrast to Goku's tempered martial artist. The contrast between Goku and Vegeta is what makes them so compelling, and changing that dynamic risks making one or both of them redundant, which is a route Dragon Ball Super authors Akira Toriyama and Toyotarou are unlikely to take.
It's a form better suited to the Saiyan Prince, who prefers brute force to Goku's more subtle techniques. However, Vegeta ultimately plays the role of Dragon Ball's bruiser in contrast to Goku's tempered martial artist. Vegeta's recent developments show a willingness to embrace a more controlled approach. Changes to this dynamic run the risk of making one or both of Goku and Vegeta redundant, which is a path that Dragon Ball Super creators Akira Toriyama and Toyotarou are unlikely to take. Goku and Vegeta's contrast is what makes them so compelling.
Furthermore, Goku's signature move, the Spirit Bomb, has been his for such a long time that it seems unlikely that other fighters will ever learn it. Even characters like Piccolo, Tien, and Yamcha who trained with the technique's inventor King Kai failed to master it when given the chance. The move is also very circumstantial, requiring several minutes and willing spirit donors to charge, so it is unlikely that the impatient and hostile Vegeta will find it appealing.