Guren Shingeki

Guren Shingeki is Kyūbi Naruto's up special move in Super Smash Flash 2.

Overview
When performed, Kyūbi Naruto quickly jumps diagonally upwards while spinning forward. The jump covers decent vertical distance with strong horizontal distance, the latter of which can be affected by using the directional inputs to affect his momentum. Opponents hit by Kyūbi Naruto as he jumps will be attacked with up to four weak hits, which deal 4% flame damage each with weak knockback.

Despite how Kyūbi Naruto has an infinite amount of midair jumps, this attack makes for an excellent recovery move, as it travels a great horizontal distance with excellent speed and does not leave Kyūbi Naruto helpless afterward; not only this, but the move can be used consecutively as many times as the player desires. However, the move deals low damage and knockback compared with Kyūbi Naruto's other attacks, so it is not as useful for attacking with.

Origin
Because of the great hatred infused in the Chakra of the Tailed Beast inside Naruto, the Red Chakra Cloak that covers Naruto’s body tends to burn anything and anyone who touches it, even Naruto himself, while shortening his lifespan in the process. When Naruto first entered four-tailed, his pain started to bleed, his blood was poured into his chakra and created a densely cloak around him.

As the series progress, Naruto has learned how to control the Chakra of his Tailed Beast, thus removing the hatred from it.

And when Naruto and his Tailed Beast, Kurama, finally found peace between each other, and Naruto gained full access to the complete immeasurable power of his Tailed Beast, Kurama’s Chakra seems to have been fully released from its hatred, thus allowing contact from others without burning them.

Trivia

 * Of all the techniques of Kyūbi Naruto, this is the only one that was not inspired neither from the manga nor the anime. Rather, this attack comes from one of Pre-Timeskip Naruto's combo attacks in the Narutimate Accel series of video games.