Overblade Mode

Overblade Mode (神刀波 (オーバーブレード・モード), Ōbāburēdo Mōdo lit. Divine Blade Surge), also known as "Seeing Red" (拝見緋, Haikenhi) is a unique Sword Magic spell, that's one of the few to not involve a sword of sorts. It increases the flow of magical power within the user's body for a few moments, enabling them to perform sword techniques and maneuvers that they would normally be unable to do.

Description
When activating the Overblade Mode, the user's willpower causes a surge within their magic origin; the magical energy being constantly pumped into the user's limbs takes ahold of the user's limbs momentarily, and breaks down the stray magical energy within the immediate vicinity. From here, the user's magic origin absorbs the components of the magical energy, and begins to pump it into the user's own body until magical energy is scattering off of their limbs. At this point, the user is capable of controlling their body as if they were in a lucid dream, as the magical energy is directed by their willpower, essentially making the user's body a puppet to their own mind. The transition into Overblade Mode is indicated by their eyes turning a haunting crimson; with red arrow-like markings manifesting underneath and above their eyes.

Because of being controlled by their own thoughts, the user's speed and reflexes are drastically increased, allowing them to make split-second movements on a whim without any prior warning; they become far above any normal magician in these fortes. In this state, the user perceives time much slower than any other magician and the like; as it seems as if the world has slowed down to an eighth of its speed. As such, when Overblade Mode is active, the user is capable of slicing objects and unprotected enemies to pieces in a split second; but only against enemies without any armour. Indeed, the user has to attack armoured enemies a bit to break up their armour and make them vulnerable. The drastically enhanced reflexes and speed enable the user to unleash powerful attacks such as Moonglade and Dancing Edge, which would normally be impossible due to the incredible reflexes and timing needed to show their full power. In any case, Overblade Mode enables the user to aim their blade at their foes more accurately, as it is a given that their strikes will rarely, if ever miss when harnessing this spell.

However, with great advantages come great disadvantages; the might of Overblade Mode is lessened by the fact that since the user is controlling their own body in a similar manner to that of a puppeteer with their puppets, they may throw away any regard to anatomically possible movements and dislocate some of their limbs—even though their limbs are controlled by magical power in Overblade Mode, the body is only human, and as such, it still suffers the same limitations as normal. As such, if the user isn't careful, they could end up being unable to continue battle after Overblade Mode ends. Another weakness is that, of course, Overblade Mode drains an enormous amount of magical power from the user's body; and as such, it is recommended that the user only harnesses it for momentary bursts of power.

Trivia

 * Overblade Mode draws inspiration from Adam's final attack in the Black Trailer from the web series RWBY, as well as Ripper Mode/Blade Mode from the video game Metal Gear Rising: Revengeance. However, the method of activation and weaknesses are different from both.
 * Overblade Mode can also be compared to the "iron sight" mode of modern shooter games.