The Deathly Hallows are three magical objects that appear in Deathly Hallows. They are the Elder Wand, the Resurrection Stone, and the Cloak of Invisibility. According to wizarding legend, they can provide mastery over death if one person owns all three. The objects are generally remembered only as part of a fairy tale called The Tale of the Three Brothers. According to J. K. Rowling, this fictional fairy tale is based on The Pardoner's Tale by Geoffrey Chaucer.

Harry eventually comes to possess all three Hallows – the cloak being inherited from his father James Potter, later understood to be a descendant of one of the Peverell brothers, the Resurrection Stone in the Golden Snitch bequeathed to him by Dumbledore, and the allegiance and mastery of the Elder Wand when he defeats and disarms its prior owner, Draco Malfoy, who unwittingly won it from Dumbledore just before Dumbledore's death.
The Elder Wand is described in Deathly Hallows as a legendary and extremely powerful wand made of elder wood with a core of Thestral tail hair. Harry discovers that the Elder Wand's allegiance is transferred when its owner is killed, defeated, or disarmed. Through a series of events, Voldemort comes to possess the Elder Wand, even though Harry is its true master. Unaware of the wand's loyalty to Harry, Voldemort attempts to duel him near the end of the novel. The wand refuses to kill Harry, with the result that Voldemort's curse rebounds on him, and he dies. After Voldemort's death, Harry uses the Elder Wand to repair his own broken wand. He then returns the Elder Wand to Dumbledore's tomb. In the film adaptation of Deathly Hallows, Harry snaps the wand in two and throws the pieces off a bridge.

J. K. Rowling revealed in an interview that the first working title for Harry Potter and the Deathly Hallows was Harry Potter and the Elder Wand.
The Resurrection Stone allows the bearer to communicate with the dead. The form of Sirius Black generated by the stone tells Harry that he and the other forms created by the stone are part of him and invisible to others. According to the fairy tale concerning the origin of the Deathly Hallows, using the Resurrection Stone drove its first owner to kill himself because he brought his late fiancée back from the dead, and she was very unhappy in the living world because she did not belong there. By the time the stone was seen in Marvolo Gaunt's possession, it had been set into a ring that bore the symbol of the Deathly Hallows, which the ignorant Gaunt believed to be the Peverell coat of arms; he used the ring to boast about his ancestry and blood purity. Harry said this is the Hallow he would desire most, as like Dumbledore he could name people he would like to communicate with again. Voldemort became …

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During the First Wizarding War, Alastor Moody lost his eye and replaced it with an enchanted glass eyeball. With the eyeball, Moody can see through solid objects, invisibility cloaks, and the back of his own head. Following Moody's death in Deathly Hallows, the eyeball ends up in the possession of Dolores Umbridge. When Harry infiltrates the Ministry of Magic, he steals the eyeball from her office and buries it in the forest.
A Foe-glass is a mirror that depicts the enemies of its owner.
The Marauder's Map is a magical map of Hogwarts created by Sirius Black, Remus Lupin, Peter Pettigrew, and James Potter while they were students at the school. In Prisoner of Azkaban, Fred and George Weasley give the map to Harry so he can travel to Hogsmeade through a hidden passageway. The map is a blank piece of parchment when not in use, but it becomes a detailed layout of Hogwarts when it is activated. It shows the locations of secret passages and instructions on how to access them. It also depicts the location of every individual at Hogwarts in real-time, including their movements.
A Probity Probe detects hidden magical objects and concealment spells. Probity Probes are depicted as thin golden rods in Order of the Phoenix. After Voldemort's return, Probes are used to protect Gringotts Bank and to scan Hogwarts students for Dark objects.
A Remembrall is a small glass orb. It contains smoke that turns red when the person holding it has forgotten something. It does not tell the holder what has been forgotten. Neville Longbottom is sent a Remembrall by his grandmother in Philosopher's Stone.
A Revealer is a bright red eraser, used to make invisible ink appear. It first appears in Chamber of Secrets when Hermione tries to make hidden writing appear in Tom Riddle's diary.
A Secrecy Sensor is a Dark detector that looks like "an extra-squiggly, golden television aerial." It vibrates when it detects concealment and lies. In Half-Blood Prince, every student and owl entering Hogwarts is inspected with Secrecy Sensors to ensure no Dark objects enter the school.
A Sneakoscope serves as a Dark Arts detector. The device is described as a miniature glass spinning-top that emits shrill noises in the presence of deception, for instance, when an untrustworthy person is near or when a deceitful event takes place nearby.
The Weasleys have a special clock in their home with nine hands, one for every member of the family. Instead of telling the time, the clock reveals the location or status of each family member. The known locations are: Home, School, Work, Travelling, Lost, Hospital, Prison, and Mortal Peril.

In the sixth novel, all nine hands point to mortal peril at all times, except when someone is travelling. Mrs. Weasley takes this to mean that with Voldemort's return, everyone is always in mortal peril, but she cannot verify this as she does not know anyone else who has a clock like hers.

Various fans have re-created the clock for their own families, for example by using geofencing for cell phones.

A Horcrux is an object used to store part of a wizard's soul, which protects them from death. If the body of a Horcrux owner is killed, that portion of the soul that had remained in the body does not pass on to the next world, but will rather exist in a non-corporeal form capable of being resurrected by another wizard, as stated in Harry Potter and the Half-Blood Prince and demonstrated in Harry Potter and the Goblet of Fire. If all of someone's Horcruxes are destroyed, then the soul's only anchor in the material world would be the body, the destruction of which would then cause final death. The creation of Horcruxes is considered the darkest of all magic.

This method was chosen by Voldemort to attain immortality. J. K. Rowling uses Horace Slughorn's expository dialogue to reveal that the creation of a Horcrux requires one to commit a murder, which, as the supreme act of evil, "rips the soul apart". After the murder, a spell is cast to infuse part of the ripped soul into an object, which then becomes a Horcrux. In the final book of the series, Hermione finds the spell in a book titled Secrets of the Darkest Art. Rowling has revealed that she intends to detail the process and spell used to create a Horcrux in her long-mentioned Harry Potter Encyclopedia.

Both inanimate objects and living organisms have been used as Horcruxes, though the latter are considered riskier to use, since a living being can move and think for itself. There is no limit to the number of Horcruxes a witch or wizard can create. As the creator's soul is divided into progressively smaller portions, they lose more of their natural humanity and the soul becomes increasingly unstable. Consequently, under very specific conditions, a soul fragment can be sealed within an object without the intention or knowledge of the creator. While the object thus affected will, like any Horcrux, preserve the immortality of the creator, it does not become a "Dark object". For example, Voldemort has unusual control over Nagini, and consequently Nagini is able to communicate with Voldemort about the presence of Harry in Godric's Hollow in Harry Potter and the Deathly Hallows.

Horcruxes made from inanimate objects cannot be destroyed by conventional means such as smashing, breaking, or burning. The known materials or objects that can destroy Horcruxes are Basilisk venom, the Sword of Gryffindor (which contains Basilisk venom after Harry uses it to kill a Basilisk), and Fiendfyre, which is a magical flame that cannot be extinguished unless it runs out of fuel.

Voldemort's creation of Horcruxes is central to the later storyline of the Harry Potter novels. Voldemort intended to split his soul into seven pieces, with six Horcruxes and the last pie…

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