The Ten Commandments is the sword that draws the inherent powers of the Rave stone. It has ten forms corresponding to the nature of the stone's ability being summoned. Only the Rave Master has the ability to wield the weapon, and only when the Rave stone is incorporated onto the sword will it work. Galein Musica forged it to be originally Shiba Roses' sword, but the latter eventually lends it to Haru Glory upon his succession of the title of the Rave Master.
In its normal state, the Eisenmeteor, the Ten Commandments is a huge sword with a slot in which the Rave stone is inserted. Its rain-guard is triangular, with intricate patterns embellished on it. On its central ridge are the words "Eisenmeteor". The sword vertically reaches Haru's torso, and save for the Rave Masters who are capable of wielding it easily, the sword, true to its appearance, is relatively heavy.
First Form: Eisenmeteor
This is the normal configuration of the sword, and will manifest even if Rave is not embedded into the sword. Eisenmeteor is a regular metal sword with no special abilities. It is, however, especially bulky, and is able to cut through magic shielding without resistance, useful against magic-using opponents.
Second Form: Explosion
Haru first draws the Explosion sword in his final battle against Feber. It is not meant for cutting but rather, true to its name, creates small explosions on contact. Upon inserting the Rave stone, the Ten Commandments changes into its first form, Explosion, and initiates the blast that destroys Feber's Dark Bring, Full Metal.
- Super Explosion: A technique where Haru charges at an opponent wielding Explosion and creates an a Explosion. First used against Go.
- Explosion Technique: Bakugeki Dance Explosion: A technique where Haru unleash multiple explosion on an opponent. First used as finishing move on Go.
Third Form: Silfarion
After Haru obtains the Rave of Knowledge from Deerhound, Haru gains supersonic speed where he can unleash multiple attacks in seconds. He first uses it against Dr. Schneider. The flaw with this weapon is that it does not have much offensive power, mainly due to making Haru lighter and thus weakening each attack.
Fourth Form: Runesave
Haru's sword can seal magic and cannot cut physical objects. It just becomes intangible when slicing into objects. He first use the sword against Sieghart and eventually use the sword to save Elie by temporarily sealing her Etherion powers.
Fifth Form: Blue Crimson
These are Haru's only dual sword where one is ice and the other is fire. He first uses this sword against Let Dahaka after Let breaks Haru's Explosion in half.
Sixth Form: Melforce
Known as the Vacuum Sword, it can either blow one's enemy away or paralyze the enemy. After witnessing King's Melforce sword, Haru obtains the sword and uses against King in his human form.
Seventh Form: Gravity Core
Known as the Gravity Sword, this sword is extremely heavy, allowing the wielder to break through hard objects. Haru usually jumps before switching to this form in order to take full advantage of its weight.
Eighth Form: Million Suns
Known as the Solar Blade, it can destroy darkness with its holy light. Haru first uses the sword to defeat Pumpkin Doryu.
Ninth Form: Sacrifar
Known as the Bloodlust sword, it grants the user extreme power after taking all the user's emotions except for anger. Shiba was thought to be able to control this sword, though any others who wield it become possessed by it.
This is Shiba's exclusive sword which he used in the Symphonian war.
Realizing that Haru cannot access the Ten Commandment's final form, Hamrio Musica forged the Ravelt with the aid of Niebel. He combined the Etherion-imbued ore Galein Musica used to forge the original Ten Commandments with a drop of his bonded silver. The forging is uniquely customized for Haru, since Musica used his silver claiming abilities and risked his life to finish it. Ravelt is representative of the bond between Haru and his allies, and is the ultimate form of the Ten Commandments, utilizing the full power of Rave. After Haru acquires the Ravelt, it becomes the default configuration of the Ten Commandments.
- It is known as the Decaforce in the English anime adaptation and Ten Powers in the English manga version.
- A weapon of the same name appears in Hiro Mashima's latest work, Fairy Tail. In the series, Erza Knightwalker employs a magic staff that changes forms, depending on the nature of the ability Knightwalker wishes to draw out. The staff shares the name and abilities of the Rave Master's sword, save for Gravity Core. In addition, Knightwalker's weapon is not known to posses the forms of Eisenmeteor, Million Suns, and Sacrifar.