«Rage Spike» is a charge-type skill that allows the user to close a distance of about ten meters in nearly an instant and consists of an upward slash from the right. However, as it is a basic skill, it deals a very insignificant amount of damage. The skill is similar to «Sonic Leap», except that it has a larger range and its trajectory cannot be aimed towards the sky.
The skill can be activated by keeping the body low and bent forward while placing the sword in a parallel manner to the user's right leg and then drawing the sword back.
Kirito used «Rage Spike» to charge at Illfang the Kobold Lord before it was able to activate Tsujikaze, because it would be impossible to keep up with that skill after it was launched. Due to the two skills clashing, both Kirito and Illfang suffered a recoil, knocking the two apart. This delay allowed Asuna to use «Linear» on the boss.
Kirito used this skill to test whether Heathcliff was actually an avatar controlled by Kayaba Akihiko. He was able to avoid Heathcliff's shield, but before the sword reached Heathcliff's chest, an invisible wall stopped the attack and an "Immortal Object" prompt appeared exposing his true identity to everyone who saw it.
Though the latest debut of Rage Spike features an upward slash from the right, earlier publications describe the Sword Skill as having the trajectories of a single outward thrust and an upward slash from the left.