"X of Swords" is a comic book crossover event which debuted in September 2020, being published by Marvel Comics. It is the next crossover event featured in the "Dawn of X" relaunch after the House of X and Powers of X event. X of Swords was followed by the Hellfire Gala event.
Plot
Lead-up
It is revealed that human ally Moira MacTaggert is actually a reality-warping mutant whose power is to live many "lives". In her ninth life, she allied with Apocalypse and they both rescued the First Horsemen.
Cypher and X travel to the mutant island of Krakoa to establish the future foundation of their mutant paradise. Communicating with Krakoa, Cypher reveals its secret history.
X and Magneto invite all former mutant villains to live on the island including immortal Egyptian mutant Apocalypse (En Sabah Nur). Both Krakoa and Apocalyse interact subtly - a hint of their shared past.
As part of the "Fresh Start" relaunch, an extra-sized issue in celebration of the long history of Marvel Comics includes a one-page story shows Apocalypse reminiscing about his original Four Horsemen who were lost so long ago.
As part of the "Dawn of X" relaunch, Cyclops, Rachel Summers and young Cable travel to a mysterious island on the ocean, where they meet enigmatic character Summoner. It is then revealed that the island is a fragment of Krakoa, with which the living island reunited with at the end of the issue. Weeks later, Summoner recounts the story about the separation of Krakoa and Arakko, while battling the demonic forces of Amenth.
In the new Excalibur title of Dawn of X, it is shown that Apocalypse wants to tap into the magical spring source that is Otherworld ruled by Omniversal Majestrix Saturnyne. This new approximation of Krakoa's mutants and the inhabitants of Otherworld sets the stage for a future confrontation. Some time later, Apocalypse gathers his fellow X-Ternals, and sacrifices some of them to create a portal to connect Krakoa to the Otherworld and Amenth.
Main story
The invading army
It is discovered that the first incarnation of the Horsemen are actually the biological children of Apocalypse and his wife Genesis who was also sent with Arakko. Following that, Apocalypse went to the Summoner and directed him to the portal to Otherworld where he could return to Arakko, while being accompanied by Unus and Banshee. However, what Apocalypse didn't expect was that this was all an elaborated plan created by his own children so they could return and overthrow Krakoa with their fellow Arakki mutants and Daemon army. Apocalypse himself was soon attacked and critically injured by his daughter War, being forced to retreat back to Krakoa to heal their wounds and prepare for war between the two groups.
Failure of the Resurrection Protocols
Former student Rockslide suffers a surprise attack by Summoner, who dilacerates his psychic essence. Hurrying back to Krakoa, the Five proceed to restore his physical husk, but, when X begins to telepathically download his memories, the five Cerebro mainframes fry and short circuit. Apprehensive, the Five convene with the Quiet Council to inform them that once a mutant is killed in Otherworld, this creates problems for the resurrection process.X-Factor (Vol. 5) #4. Marvel Comics.
The gathering of swords
Polaris (Lorna Dane) acts as a medium and delivers the list of swords and cryptic hints about the chosen champions of Krakoa. Magik is the first one to rise to the occasion.
Wolverine and Arakki mutant Solem are sent to a Hell-like dimension to reach legendary bladesmith Muramasa, and ask him to forge new blades for the tournament. Solem gets both of the new Muramasa swords, but yields one to Logan on a yet unrevealed price.
Storm travels to Wakanda to request permission to borrow an ancient relic from the Royal Family: a mystical sword named Skybreaker, made of vibranium and previously wielded by a legendary Wakandan king. Due to the Royal Family's refusal, Ororo is forced to steal it only to face her ex-husband T'Challa, before leaving the country.
In Krakoa, Cypher (Doug Ramsey) shares his worries with Warlock and the Living Island, while training under Magik for the upcoming tournament. Meanwhile, the Quiet Council decides to take a different approach instead of sending a mutant with little battle experience: they agree to send Mister Sinister and his Hellions on a secret mission to sabotage the contest.