How Boruto Completely Changed Naruto's Signature Attack
Over the course of Naruto's expansive story, protagonist Naruto develops or otherwise makes use of a wide variety of signature techniques. In the series sequel Boruto, for example, Naruto is able to access the previously untapped potential of the Nine-Tailed Fox spirit within him, attaining a power-up known as the Nine-Tails Suicide Form.
Among Naruto's signature attacks is the Rasengan. Naruto first learns the ability from Jiraiya, his first proper mentor. The Rasengan is essentially a swirling orb of Chakra energy amassed in its user's hand. The high concentration of raw power within each Rasengan is deadly. However, learning to gather a large amount of energy into a small area is difficult for most characters. Only a handful of ninja throughout the entire Naruto series have ever been able to learn to use the ability.
In addition to becoming a key part of Naruto's combat arsenal, the Rasengan is spun off into more advanced techniques, generally by Naruto, on numerous occasions. The Spiralling Strife Spheres technique, for example, is something of a showcase for Naruto's accumulated abilities. First, he enters his Nine-Tails Chakra Mode, then he uses synthetic arms manifested from his chakra energy to create multiple Rasengan above him.
Among the ninja capable of using the Rasengan is Naruto's son, Boruto. In his titular series, Boruto doesn't simply use the Rasengan as his father once did before him. Instead, he puts his own twist on the iconic technique.
Boruto created the Compression Rasengan
Boruto first learns the Rasengan while training under his mentor Konohamaru, who was once himself the apprentice of none other than Naruto. When Boruto first successfully creates a Rasengan, however, it doesn't resemble the technique as used by Naruto but includes a lightning element. Thus, Boruto's version of the Rasengan is known in full as the Vanishing Rasengan.
Later on, after making use of the Vanishing Rasengan over the course of a few story arcs, Boruto puts a new spin on the technique. His second innovation is called the Compression Rasengan. In essence, Boruto forms a Rasengan in both hands held close to one another. The two overlapping sources of energy are thus compressed into one concentrated point. The end result is a smaller but more potent attack.
Much of Boruto's story is concerned with legacy. Its heroes and villains alike are oftentimes defined by their relationship to events that took place or were depicted in Naruto before it. By innovating on Naruto's signature technique, not only is Boruto highlighting his connection to the prior series' main character as his son, but he is also demonstrating that he is someone capable of innovating on a legacy passed down to him from one of the greatest ninja in his fictional world's history.