The most recent X-Men event story, X of Swords, features a group of mutants from Krakoa entering into the realm of Otherworld to do battle with mutants from Arakko. The various X-Men are known as the Swordbearerers of Krakoa, called such because they bring ten swords with them, each one unique and special in some way.
They fight for the fate of Krakoa, and of Earth, opposing Arakki mutants whose ranks include Apocalypse's ex-wife and his four children. While the Swordbearers of Krakoa are all skilled masters of martial arts (with one notable exception), their weapons are just as impressive.
10 Light of Galador
Cable recently acquired this sword while traveling through space, made from the rare metal known as Plandanium, which was used by the alien Galadorians. The chief warriors of Galador were cyborgs known as Spaceknights, and the Light of Galador was one of their swords.
Space swords are objectively cool. But the Light of Galador is also a powerful energy conductor that can store multiple zetabyes of data, making it a high-tech piece of equipment.
9 Scarab
Apocalypse’s sword is a khopesh which he wielded in ancient Egypt. It was forged millennia ago by the mutant Isca the Unbeaten (whose power is that she cannot be defeated).
Scarab is composed of four separate pieces, each one made from Red-Gold Iron to honor the birth of each of Apocalypse’s children (otherwise known as the Four Horsemen of Apocalypse). The blade is sharp enough that it impressed Gorgon, while it is possessed of a palpable sense of sorrow.
8 Warlock
Warlock is a techno-organic alien known for his close association with the New Mutants (and Doug Ramsey in particular). He is an all-around awesome character, known for his irregular styles of speech, his deep caring for others, and his inseparably close friendship with Doug.
Warlock recently used his shapeshifting abilities to turn himself into a sword so he could accompany Doug into Otherworld, as Doug had been chosen as one of the Swordbearers of Krakoa. However, just because Warlock is awesome does not mean he will make all that great of a sword (or that he will be able to assist Doug, who is a less than stellar swordsman).
7 Sword of Might
The Sword of Might is a magical item that was supposedly forged in the fires of creation that made the universe itself.
When Merlin wishes to choose a new Captain Britain, he gives them a choice between two items: the Amulet of Right and the Sword of Might—items embodying the concepts of life and of death. Brian Braddock became Captain Britain after choosing the Amulet, but he has since stepped down, assuming the mantle of Captain Avalon and now wielding the Sword he passed up on so long ago. While it has been forged in the fires of creation, at the end of the day, it is still just a sword. The powers it conveys seem to be more impressive than the weapon itself.
6 Starlight Sword
The Starlight Sword was made from the walls of the Starlight Citadel, a great tower that sits at the nexus of all the different multiverses. Saturnyne, who rules over the Starlight Citadel and bears the impressive title of Omniversal Majestrix, has said that that it has doors to all of the different realities built within it (though just what that means in practical terms is yet to be explored).
Unfortunately, not a lot has been seen with this sword in action. Shortly after Betsy Braddock (the new Captain Britain) began wielding it against the mutant Isca the Unbeaten, Isca lived up to her name. Betsy broke into pieces like shattered glass and seems to have blinked out of existence. Hopefully, the sword carried her to another reality to spare her life, but there is no way to be certain.
5 Muramasa Blade
Based on the real-life swords made by the historical swordsmith Sengo Muramasa, the Marvel versions of these weapons have been designed with a piece of a person’s soul. The Marvel version of Muramasa made a sword for Wolverine with a piece of his soul in it, but more recently, the smith forged a pair of identical blades with his own soul, using the fires of hell as his furnace.
These blades can cut through adamantium and can inflict wounds that no healing ability can recover from. Even the great Beast of the Hand covets Muramasa’s weapons.
4 Godkiller
At this point, every item in the list can be debated, given the unfathomable power of the weapons. Since previous entries included a sword made from the nexus of reality and one so powerful that a demon coveted it.
The Godkiller was made during the war between the Japanese gods and the Greek gods. This sword was made to kill the gods, bleeding the immortals and sending them to the netherworld. While this weapon is immensely dangerous, the very fact that it is flawed means there are some limits to it.
3 Magik’s Soulsword
Ilyana Rasputin is better known by her superhero name Magik. As a small child, she was trapped in Purgatory (a domain of Hell) and had to learn sorcery to survive. She also forged her very soul into a blade, known as the Soulsword.
The Soulsword is not just an incredibly dangerous melee weapon, but is also a powerful magical device. It can cut down magical entities, break or counter powerful spells, and even strike enemies who have no physical form. It also enhances and augment’s Ilyana’s magical abilities and can conjure up protective armor for her.
2 Skybreaker
This weapon is the most valued item in all of Wakanda. When the first Wakandan king entered the Great Vibranium Mound that had been impacted by a falling object from space, he forged a sword in the fires of a volcano.
Skybreaker is not merely vibranium, but was irradiated in the supernova that sent the purest of vibranium hurtling across space toward Earth. It can channel blasts of energy, and the blade cannot be dulled by conventional means. Arguably, this weapon is the very soul of Wakanda, more powerful than any other vibranium weapon created since.
1 Grasscutter
Grasscutter is the perfect sword—literally. During the war between the Greek and Japanese pantheons, two swords were created. One was Godkiller, a weapon whose name revealed both its purpose and its potency.
But the other sword, Grasscutter, was flawless, a work of sheer perfection. It was given to the evil god Amatsu-Mikaboshi, also known as the Chaos King. The sword eventually found new owners, and along with its twin, is now in the hands of the mutant Gorgon.