It looks like a regular purple cane, with the hilt of the sword also serving as the handle of the cane.
Not much is known about the quality of this sword itself, except that Brook mentioned the Longarm Tribe sharpened the sword during the timeskip. Additionally, Brook is able to enhance its power by enveloping the blade with his soul using his Devil Fruit ability. The energy of his soul brings the "very cold of the underworld into this world", resulting in the sword being freezing cold. Due to this feature, Brook gave it the epithet of "Freezing Sword" (凍える剣 Kogoeru Ken?). He would utilize this enhanced blade with his graceful swordsmanship.
Brook uses an unnamed form of swordsmanship that resembles classical fencing (フェンシング fenshingu?). Its attacks consist of fast cutting techniques used by Brook's Kingdom's Assault Squad. The majority of the techniques are named after songs and dances coupled with fencing terms usually spoken in French but they sometimes make use of Japanese.
This sword discipline was also used by Ryuma (due to Brook's shadow that was in him), who had also demonstrated most of the known attacks at a level far superior to Brook's. While these techniques are deadly in the hands of a "speed-type" swordsman like Brook, it has been shown to be absolutely destructive when used by a "power-type" swordsman like Ryuma.
- Hanauta Sancho: Yahazu Giri (鼻唄三丁矢筈斬り Hanauta Sanchō: Yahazu Giri?, literally meaning "Three-Verse Humming: Arrow-Notch Slash"): The user slashes an opponent at such a fast pace that it appears that they did not attack at all (in fact, to the casual observer it would look like the user simply walked past the victim). Only when a certain amount of time has passed, which is approximate to the time the user walks ten feet away, or three meters (verses, as the name suggests), does their opponent realize the attack. It seems to employ elements of iai (instant sword-draw-and-resheath) since it is generally initiated (though not always) with the user moving towards the intended target(s) with an unsheathed blade and walking past them before sheathing it back. It is usually at this point that the victims start manifesting and feeling the effects of this high-speed attack. The actual attack itself, however, is never seen clearly due to the speed implemented. The technique is highly versatile, since with it, the user can slash multiple targets at once, and if they so wish, the damage they inflict can be as fatal or as incapacitating as they like. The latter was performed by Ryuma using the back edge of his Shusui. Also, when Brook used it against Tararan, he applied salt to purify the zombie at the same time; and it was only until the shadow inside him was expelled that Tararan realized it. In the Viz Manga, this is called Three-Pace Hum: Notch Slash, and in the FUNimation dub, it is called Three-Verse Humming: Arrow Notch Slash.
- According to Brook, this was originally named "Requiem la Banderole" (鎮魂曲 (レクイエム) ・ラバンドゥロル Rekuiemu Ra Banduroru?, Requiem Lebanderole in the Viz Manga) and was a fast cutting technique that he learned from his kingdom's "Assault Squad". It was given its current name by his comrades and was praised by them. This technique was first seen being used by Ryuma on Nami, Usopp, and Chopper in Hogback's lab, where it was used to render all three unconscious. This was first seen being used by its original practitioner, Brook, against Tararan. Its original name comes from Requiem, which is a type of song sung during funerals, and Banderole, which can refer not only to a type of small flag or streamer used by knights in heraldry, but also as a reference to the fencing move Coup de Banderole, when the attacker performs a lateral slash against the opponent's chest, leaving a "stream" mark, hence the name "banderole."
- Aubade Coup Droit (夜明歌 (オーバード) ・クー・ドロア Ōbādo Kū Doroa?, literally meaning "Dawn Serenade: Right-Handed Strike"): A thrusting technique, the sword creates a highly compressed blast of air with enough power to burst its way through a thick wall as if fired from a gun. Powerful as it is, it could just as easily be countered by a similar attack as demonstrated by Zoro with his Pound Ho. This was first seen being used by Ryuma. According to Brook, this technique does not do as much damage when he uses it. Aubade is a poem or song of or about lovers separating at dawn. Coup Droit means right handed strike in French.
- When Brook uses this technique after the timeskip, its strength was at least comparable to Ryuma's, as it launched a compressed blast of air powerful enough to break through ice, something he was not able to do before. This stronger version was first seen used against the wandering torso of Kin'emon found in Punk Hazard.
- Prelude: Au Fer (前奏曲 (プレリュード) ・オフエル Pureryūdo Ofueru?, literally meaning "Prelude to Iron"): The user slashes an opponent's weapon almost instantaneously. Apparently intended to disarm the opponent by destroying whatever weapon they might be wielding at close range. This was first seen being used by Ryuma against Zoro. Prelude comes from the prelude found in music. Au Fer comes from the fencing term Attaque Au Fer, which is a basically attacking an opponent after hitting their sword with one's own.
- Gavotte Bond en Avant (革命舞曲 (ガボット) ・ボンナバン Gabotto Bonnaban?, literally meaning "Gavotte: Leap Forward"): A thrusting technique, the user propels himself forward in order to strike an opponent. As demonstrated by Brook, this move can be done even in mid-air. This was first seen being used by its original practitioner, Brook, against Oars in a combo with Usopp, Nico Robin, and Nami. Gavotte comes from a fast-paced French folk dance. Bond en Avant is French for "Leap Forward" and is a technique in fencing, usually used to propel oneself to their opponent to attack.
- When Brook used this move after the timeskip, its strength was much greater, making a creature such as a dragon bleed (a great testament to his strength as that dragon's hide was said to be stronger than the bigger dragon which required Zoro's Shishishi Sonson to cut through it) and it can be combined with his freezing powers to leave ice on impact. This stronger version was first seen being used against the dragon inside Caesar's laboratory with Kin'emon.
- Polka Remise (酒樽舞曲 (ポルカ) ・ルミーズ Poruka Rumīzu?, literally meaning "Polka Continuation"): The user delivers several thrusts against an opponent. Visually, due to the user's speed, it looks as if they are thrusting with several swords. When used by Ryuma in the anime, a barrage of purple-colored compressed air bullets are launched at the opponent. This was first seen being used by Ryuma against Zoro. The technique is named after Polka, a type of dance and genre of music originating from Bohemia. Remise is a fencing term referring to the continuation of an attack after initially missing or parried.
- Swallow Bond en Avant (飛燕 (スワロー) ボンナバン Suwarō Bonnaban?, literally meaning "Swallow Leap Forward"): An aerial version of Gavotte Bond en Avant, Brook first positions himself in mid-air several feet above his target and then performs a descending Bond En Avant spinning downwards in an attempt to spear his target. Like Zoro's Shishi Sonson, this technique managed to tear its way through a Pacifista's outer covering, but not the armor beneath it, and left significantly less damage than Zoro's Shishi Sonson. This was first seen being used against PX-4. "Swallow" is a reference to the bird as this technique an extremely fast air-based attack.
This is a list of the techniques he uses after his two years of training, touring around the world and learning about the true nature of his Devil Fruit powers. After the timeskip, Brook manages to control the energy of his soul and is even able to bring the "very cold of the underworld" to his attacks. By doing this, his attacks gain freezing effects and he can combine his techniques with his musical abilities too.
- Quinte Tierce Fantasia (キントーティアス幻想曲 (ファンタジア) Kintō Tiasu Fantajia?, literally meaning "Fifth Parry and Third Parry Fantasy"): Used in conjunction with Party Music, Brook uses a swift draw-and-sheathing technique while his opponents are still under the influence of the hypnotic nature of the musical technique. The mechanics of this technique may be similar to Hanauta Sancho: Yahazu Giri. This was first used against some of the New Fishman Pirates. Quinte and Tierce are words describing two different types of fencing parries, and may imply how Brook moved his arm in order to use this technique. They also are two types of note spacing Quinte being a five notes space and Tierce being a three notes space. So far, this is the only new technique of Brook's that does not freeze.
- Kasuriuta: Fubuki Giri (掠り唄 吹雪斬り Kasuriuta Fubuki Giri?, literally meaning "Pastoral Song: Blizzard Slash"): Combining his incredible speed and his Devil Fruit ability, Brook does the same thing Yahazu Giri does but he sheaths his sword from top to bottom and the streak mark he creates with his "chilled" sword freezes the opponent's blood. Brook claims that the wind produced from his sword's slashing in this technique contains the essence of the chilling winds of the underworld itself. This was first used to defeat Zeo. In the Viz manga and FUNimation subs, this is called Song of Scratches - Blizzard Slice.
- Ekakiuta: Hitoyogiri (絵描き唄 一節斬り Ekakiuta Hitoyogiri?, literally meaning "Drawing Song: One-Joint Slash): This is another swift draw-and-sheathing technique and it slices the opponent's torso with three horizontal freezing cuts. It was used to defeat Jora. In the Viz manga and FUNimation subs, this is called Painting Song Bamboo Flute Slice. Ekaki Uta is known to be a song for children in Japan that teaches them how to draw an animal or any other figure, while hitoyogiri is a musical instrument with five fingerholes made from a piece of bamboo with one node. In the anime, the freezing effect is missing.
- Soul Parade (魂の (ソウル) パラード Sōru Parādo?): A defensive maneuver, Brook holds Soul Solid backhand and blocks an attack, freezing anything it touches. It was first used to defend against Sheepshead.
- Swallow Banderole (飛燕 (スワロー) バンドゥロル Suwarō Banduroru?): Brook jumps towards the opponent and performs a very swift vertical downward slash that cuts and freezes them. The freezing effect is such that it even affects the ground. It was first used to finish one of the last two remaining guards of the Room of Treasure in Whole Cake Chateau.
- Hanauta Sancho: Tyamasi no Yahazu Giri (鼻唄三丁 魂 (テャマスィー) の矢筈斬り Hanauta Sanchō: Tyamasī no Yahazu Giri?, literally meaning "Three-Verse Humming: Soul Arrow-Notch Slash"): Combining Hanauta Sancho: Yahazu Giri with his Devil Fruit power, Brook jumps into the air and uses a draw-and-sheathing technique to vertically slash his opponent. His speed and light weight allow him to jump high into the air and cut faraway opponents. It was first used against Zeus, and was strong enough to bisect the cloud homie. As the technique is imbued with soul power thanks to his Devil Fruit, it even inflicts pain on the Homie, which are immune even to the effects of Haki, and could normally only be harmed by an opposing attribute. This is called Three-Pace Hum Soul Notch Slash in the Viz Manga.
- Kakure Uta: Tsumuji Giri (隠れ歌つむじ切り Kakureuta: Tsumuji Giri?, literally meaning "Secret Song: Whirl Cut): Similar to Hanauta Sancho: Yahazu Giri, Brook walks behind his target and slashes their back twice so fast the target does not even realize it, with the culminated effect initiating once he completely sheathed his sword. Brook was proficient enough with this technique to cut just the back without cutting the long cape covering it. Brook used this to cut open a Biscuit Soldier's back in order for Pedro and him to hide in said soldier. It is called Secret Song Whirlwind Slash in the FUNimation sub.
Video-Game Only Attacks
- Rondo: Full Volte (輪舞曲（ロンド）・フル・ヴォルテ Rondo Furu Volte?): Brook repeatedly and rapidly thrusts his sword at his opponents. Then, he leaps and finishes with Gavotte Bond en Avant. It is first used in One Piece: Pirate Warriors. Rondo is a type of French music composition used in medival times. Rondos are fast and vivacious, which refers to the speed of the attack.
Brook also uses his sword to play on his violin. He can combine his swordsmanship abilities with this music and hypnotize his enemies.
Before the Timeskip
- Nemuriuta Flanc (眠り唄・フラン Nemuriuta Furan?, literally meaning "Lullaby Parry"): The user swipes his weapon over a violin like a fiddle and plays a soothing melody, which makes the user's enemies fall asleep. This allows him to score a free hit on the sleeping enemies. The main drawback, however, is that allies of the user are also susceptible to falling asleep as well. Brook's sword carries the "lullaby parry" song on its sword edge, like a violinist's bow, and creates a sleep-inducing soundwave. This was first seen being used by Brook against some Flying Fish Riders. This is called Lullaby Flanc in the FUNimation dub and Lullaby Parry in the Viz manga. Nemuriuta is Japanese for "lullaby", and Flanc is a parrying technique in fencing (Parade de Flanc), where the fencer moves his sword, hand, elbow, and upper arm in a wave/arc movement up to shoulder level with the swords edge facing to the right.
After the Timeskip
By learning the true nature of his Devil Fruit, traveling around the world during two years, he managed to feel the souls of others and combined with his music he can move them. He uses this ability to control his enemies via hypnotic music.
- Party Music (パーティーミュージック Pātī Myūjikku?): Brook uses his music to hypnotize his opponents into believing they are at a night festival. This way, his opponents not only drop their guards, but they are also made vulnerable to suggestions. This was first used against some of the New Fishman Pirates.
- Raikotsuken: Gavotte Bond en Avant (雷骨剣 革命舞曲 (ガボット) ・ボンナバン Raikotsuken: Gabotto Bonnaban?, literally meaning "Lightning Bone Sword: Gavotte Leap Forward"): After being thrown by Usopp's Kuwagata and spun by Robin with Slalom Vine, Brook, with his Shikomizue positioned vertically above his head and the blade's tip pointed at the path of his trajectory, is propelled at a large opponent through a cloud created by Nami's Dark Cloud Tempo. Upon being electrocuted by the cloud, Brook is turned into an arrow of lightning. Brook then thrusts through the opponent with Gavotte Bond en Avant, further propelling him. The opponent is then shocked as well as stabbed by the attack. The only drawback to this attack is that, after being shot through an opponent, Brook does not have any control of where he goes next. This was first seen being used against Oars.
- Fencing - Wikipedia article about fencing.
- Fencing terms - Wikipedia article that lists commonly used terms in fencing.
- Classical Fencing and Historical Swordsmanship Resources - An extensive directory of traditional fencing groups and individuals.
-  - A large online fencing community.
- Requiem - Wikipedia article about a requiem in general.
- Banderole - Wikipedia article about a banderole in general.
- Aubade - Wikipedia article about an aubade in general.
- Prelude - Wikipedia article about a prelude in music.
- Gavotte - Wikipedia article about gavotte.
- Polka - Wikipedia article about polka.
- Rondo - Wikipedia article about rondo.
- Lullaby - Wikipedia article about lullabies.