Dragon Ball Super's Tournament of Power story introduced Caulifla, the anime's first-ever female hero to reach the Super Saiyan transformation. Caulifla is actually the first of two female Super Saiyans, the other being her best friend Kale, a character who achieves the form shortly after Caulifla.
Over the course of 131 episodes, Dragon Ball Super added several new heroes and villains to Dragon Ball canon, with the bulk of them being introduced in the Universal Survival Saga. The saga's main event, the Tournament of Power, gave Goku and his Universe 7 team a whopping number of 70 combatants to fight. The new characters included warriors like Jiren, Dyspo, Ribrianne, a pair of Namekians from Universe 6, and more. One of these many new additions was Caulifla, a character whose main opponent in the tournament was Universe 7's primary champion, Goku.
Who is Caulifla? Caulifla, who first appeared in episode 88 of Dragon Ball Super, is a character from a completely different universe than Goku's. Caulifla hails from Universe 6, the home of Hit, Cabba, and Frost. Originally depicted as a Saiyan "punk" who does whatever she pleases, Caulifla was sought out by a fellow Saiyan named Cabba, who wanted to recruit her to compete in a tournament between the strongest fighters in the universe. After meeting Caulifla, Cabba — who learned how to become a Super Saiyan from fighting with Vegeta — taught her how to become a Super Saiyan without triggering her anger. After learning how to channel her energy through her back, Caulifla was able to use this method to become the Dragon Ball franchise's first female Super Saiyan.
Caulifla was selected to be one of Universe 6's ten warriors for the Tournament of Power. For most of the fighting, Caulifla was paired with Kale, with whom she shared a sisterly relationship. Caulifla's primary focus during the tournament was defeating Goku because, like most Saiyan warriors, Caulifla's goal is to improve and face off against the strongest adversaries around. The confident and ambitious Saiyan couldn't beat Goku, but she did succeed in at least impressing him with her power. As a duo, Caulifla and Kale survived through most of the fighting, and both were involved in an intense battle with a weakened Goku in the second half of the tournament.
There reached a point in the tournament when Caulifla and Kale had to combine their power and fuse to become "Kefla," making them only the second pair of Saiyans to use Potara fusion. As Kefla, the two Saiyans were so powerful that Goku had to use his incomplete Ultra Instinct form to eliminate them from the tournament. In the manga version, though, Kefla was taken down by Gohan instead.
Though Universe 6 ultimately lost, she was one of the team's most valuable members. It's also worth noting that Caulifla's battles with Goku in the Tournament of Power caused her to rapidly increase in power until she was able to reach another level: Super Saiyan 2. Super Saiyan 2 is as far as Caulifla ever got in Dragon Ball Super, but the gains she was able to make in such a short time say a lot about her potential in the franchise's future.