Excalibur

Unlike other weapons, he transforms into a unique, non-humanoid creature that is difficult for humans to comprehend.

In the anime, he is known for wearing a hat that is actually a "top-quality British-made norimaki (sushi roll)."

He is an immensely prideful and eccentric being, with his personality often described as "shattered."

To become his Meister, one must follow 1000 of his absurd rules, which results in him controlling nearly 90% of their life.

Though his Soul Wavelength is compatible with any Meister, his impossible personality ensures no one can truly get along with him.

He has many irritating habits, such as sneezing repeatedly, which was the final straw for his one and only temporary partner.

His true identity is one of the Great Old Ones, specifically the Great Old One of "Wrath."

He is the "one other person" mentioned by the Great Old One of "Power" when listing the remaining members of their kind to Death the Kid.

This hidden truth is subtly hinted at within one of Excalibur's own long-winded speeches.

According to Lord Death, Excalibur is the original "weapon with a soul," the very concept that inspired the creation of all Demon Weapons.

Eibon used him as a model to create the first prototypes of modern Demon Weapons.

However, Eibon, the inventor of Demon Weapon technology, loathed Excalibur and vehemently denies this history.

He is introduced as the most powerful weapon in existence, bestowing phenomenal strength upon his wielder.

Anyone who wields him gains wings of light, the ability to teleport, and the power to slice through space itself with a single swing.

The bumbling Meister, Hero the Brave, was the only person to successfully complete all 1000 tasks and wield him.

Hero was unable to tolerate Excalibur's habits and dissolved their partnership almost immediately.

The fairies living in his cave were so annoyed by his personality that they threw a festival to celebrate when Hero finally took him away.

He has a one-sidedly negative relationship with Eibon, who despises him.

He greatly frustrated the members of Spartoi, as having a normal conversation with him proved impossible.

Liz Thompson briefly wielded him, but under the influence of "Pride," she promptly threw him into a dimensional rift.

He was present for Lord Death's final moments and promised to fulfill his last wish to "watch over my sons."

He later offers encouragement to a despairing Death the Kid, helping him cope with the truth about his father's death.

It is said that anyone who can successfully master him, despite his broken personality, is a true hero in their own right.

This is why, despite being accessible to all, he remained stuck in his cave, untouched by anyone.

"Fool!!"

The Unwieldable Sword

Excalibur is a legendary sword who remained lodged in a stone deep within a cave, available for anyone to take.

However, because of his ridiculously demanding personality and the 1000 rules he imposes, no one could ever successfully partner with him.

A Brief Partnership

A bumbling Meister named Hero the Brave managed to effortlessly complete all 1000 tasks and wield Excalibur's power.

With this strength, he easily defeated Black☆Star, Death the Kid, and Kilik Rung.

Ultimately, Hero couldn't stand Excalibur's personal habit of "sneezing repeatedly" and gave him up, ending their partnership.

Inside the Book of Eibon

Trapped within the Book of Eibon, he appeared in the "Chapter of Wrath," where his inability to hold a conversation irritated the members of Spartoi.

Later, in the "Chapter of Pride," Liz wielded him briefly, but her inflated ego caused her to slash open space and discard him into the void.

Unscripted Appearances

He once dramatically burst into Lord Death's room simply because he "felt like you were talking about me" when his name was mentioned.

During the Lunar War, he stood by Lord Death's side, watching over the battle from afar.

The Final Watch

After witnessing Lord Death's last moments, he honors his final request to watch over his sons.

When Death the Kid falls into despair upon learning his awakening caused his father's death, Excalibur appears to offer him words of encouragement.

In the manga, he is known for breaking the fourth wall in various ways to annoy the reader.

This includes delivering long speeches, talking over other characters, multiplying to obscure panels, and even placing his dialogue between pages.

Following the anime episode in which he first appeared, the series' official website was "hijacked" by him.

In episode 17, he continued to sing a song from the end of Part A all the way through the mid-episode commercial break.