Excalibur

is a bladeless sword and the personal weapon of Arthur Boyle. If wielded by a Third Generation, the user can mold a concentrated blade of plasma in place of the blade.

Appearance
Excalibur is a peculiarly designed sword, consisting of only a white hilt. The hilt features a handle with white spiraled tape around it, and a cross at the top resembling that of the cross used by the Special Fire Force. The plasma is emitted from the top of this cross in turn of where the blade of the sword usually is, forming a plasma-blade, that shines a blue aura when activated. It's sheath is white.

Arthur also possess miniature version of Excalibur's hilt that he can use like knives to make smaller cuts. However, these miniature hilts have poor heat resistance and will melt after only a single usage.

The new Excalibur forged by Vulcan has a much more elegant design than the original. Consisting of a black handle with a pommel that is topped by a rounded guard that comes to a point. The new blade hilt much more resembles one they may have been used by a medieval knight or king.

Overview
As matter increases in temperature, it passes through the solid, liquid and gaseous states, and once at a high enough temperature, the matter reaches a state of plasma. Such process requires the wielder to use their Ignition Ability to increase the temperature of their flames to this point. As noted by Takehisa Hinawa, the swordplay using Excalibur is equivalent to plasma cutting.

Arthur exclusively uses Excalibur with his right hand. While fighting with Excalibur in his left hand, Arthur loses all ability to fight with a sword, due to his simple-mindedness. Sometimes the cuts are so fine that when he cuts through objects, the part that was cut doesn't fall through. Excalibur has shown the proficiency the ability to deflect and fend off against flames. The substance he creates cannot be easily extinguished by the Second Generation, though it can be manipulated.

When Arthur is feeling delusional and imagining himself as a medieval knight, his plasma blade becomes larger and more powerful; the more knightly he feels, the more powerful the blade becomes. The most powerful state the plasma blade has ever achieved is known as Dragon Killing Holy Sword: Excalibur, which Arthur achieved during his battle with Dragon.

Trivia

 * The weapon is named after Excalibur, a legendary sword used by King Arthur.
 * According to Arrow and Flail, the blade has a very powerful will of fire.