A Horcrux is a powerful object in which a witch or wizard has hidden a fragment of his or her soul for the purpose of attaining immortality. Creating one Horcrux gives one the ability to resurrect oneself if the body is destroyed; the more horcruxes one creates, the closer one is to true immortality. Creating multiple Horcruxes is suggested to be costly to the creator, by both diminishing their humanity and even physically disfiguring them.
The first Horcrux was created by Herpo the Foul. The only other known creators of them were Lord Voldemort and Hadrian Reveroak. In fact Lord Voldemort created seven horcruxes and Reverook created three. Professor Slughorn mentioned that the fate of those who use Horcruxes to survive is what only few would prefer, suggesting that few others have created their own Horcrux.
The nature and concepts of Horcruxes are so terrifying, they were kept secret from most of the wizarding world, and only few ever knew what they were. Hogwarts banned the subject of Horcruxes, and even books such as Magick Moste Evile would skim the subject at best. The only known book that explains Horcruxes in detail is Secrets of the Darkest Art. The subject being vague, nobody knew what the effects of creating more than one Horcrux would be like, as none of them, aside from Voldemort and Revercroak, have done so.
Creation of a Horcrux is considered the foulest act of Dark magic, as it attempts to violate and tamper with the multiple laws of nature and morality in its creation. Horcruxes are objects considered to be so evil that even the texts published explicitly to cater to the practise of the most terrible kinds of magic will not speak of them. Even Magick Moste Evile skirts the topic. It is a banned subject in Hogwarts School of Witchcraft and Wizardry.
The only known book that provides specific instruction on the creation of a Horcrux is Secrets of the Darkest Art, once held in the Hogwarts Library. Due to the book's extremely dark and dangerous nature, Albus Dumbledore had it hidden away in his office; he did not destroy it, however.
The specific processes involved are known to involve a spell and a very horrible act. To split one's soul, one must also commit the most supreme act of evil — murder — and then encase a portion of their fractured soul into a chosen object with an as-of-yet unrevealed spell. The detached soul fragment will always remain as it was when it was divided; for instance, Tom Marvolo Riddle's diary portrayed Tom Riddle as a teenager.
Though a Horcrux can be made from anything, Lord Voldemort chose to use objects of great significance or importance. The process makes the part of the soul remaining in the witch or wizard unstable. If the maker's physical body is later destroyed, he or she will live on in non-corporeal form, although there are methods of regaining physical form. However, according to Professor Horace Slughorn, few would want to live in such a form and death would be preferable.
It is stated at one point that Voldemort had already "pushed his soul to the limit" in creating his seven Horcruxes. This implies a finite number of Horcruxes any one person may create before the process becomes too dangerous to attempt again. Though this limit is never explicitly stated, the number seems to set solidly at seven intentional Horcruxes, and creating seven Horcruxes in addition to the person's own body renders the soul unstable and liable to break off when the person whose soul it is commits murder.
The creation of a Horcrux can be reversed by its creator by a true feeling of remorse, though the effects of this can apparently be painful to the point of being fatal.
Interestingly, since Professor Dumbledore said that "there is no help possible" for Voldemort's soul, it may be that any soul as badly damaged as Voldemort's could no longer be repaired through remorse as described in Secrets of the Darkest Art. Alternately, and more likely, the soul can still be repaired through the redemptive power of repentance. Harry told Voldemort to "try . . . be a man. . . try for some remorse. It's your one chance. It's all you've got left." This seems to indicate that though Tom Riddle's soul is maimed and seriously injured, he can still repair it by regretting all the horrible things he did; Dumbledore may have simply meant that Voldemort was incapable of remorse to save his own soul.
Horcruxes can also be destroyed. If a person's body was destroyed, his or her soul would remain intact, whereas with a Horcrux it is the opposite, as the piece of soul depends upon its container to survive. Destruction of a Horcrux is difficult, but not impossible, and requires that the receptacle to be damaged completely beyond physical or magical repair. When a Horcrux is damaged to this point, it may appear to "bleed" (ink in the case of Tom Riddle's Diary) and a scream may be heard as the soul fragment perishes. However, as a safety measure to protect one's immortality and precious soul fragment, the creator would usually place powerful enchantments onto the artefact to prevent damage.
It is unknown if the creator of the Horcrux will be able to sense that his soul fragment was destroyed, although Professor Dumbledore stated that in the particular case of Lord Voldemort, he wouldn't feel their loss because his soul was sliced too many times and stayed that way for too long.
All known methods of Horcrux destruction are as deadly as the murder needed for its creation. For example, the earliest known method is administering basilisk venom to the Horcrux, the only cure for which is phoenix tears, an extremely rare substance. Other known methods are Fiendfyre, which requires extreme skill to control, basilisk fangs and the Killing Curse which seems to be capable of destroying a Horcrux if it is animate, given that part of that persons soul is contained in someone elses body.
The fragments of a person's soul within a Horcrux can think for themselves and have certain abilities, including the ability to influence those in their vicinity. Someone wearing or holding a horcrux can become moodier and more prone to fighting. They would also be unable to summon spells such as patronuses while wearing the locket since the soul fragment inside would darken their thoughts. A person with an affinity for the Dark Arts, on the other hand, would be strengthened by the influence of a Horcrux. If a person is more emotionally vulnerable, it is possible for the soul inside the Horcrux to take control of him or her. In this way, a Horcrux can gradually feed on another person's life or negative emotions to strengthen itself and increase the ability of the soul fragment within to act independently in the physical world. When Ginny Weasley began to transcribe her fears and insecurities into the pages of the diary, the fragment of Tom Riddle's soul contained within was not only able to write back to Ginny but eventually drained enough life out of her to actually manifest itself in a semi-corporeal form and work magic with the wand of Harry Potter. On the other hand, Horcruxes which have been isolated for long periods of time (such as Hufflepuff's Cup and Ravenclaw's Diadem) were very passive by comparison and took no real measures to protect themselves. Horcruxes also possess some last line of defence against destruction. The fragment of soul within the Horcrux seems to be able to sense impending threats and can act to defend itself. For instance, Slytherin's locket viciously taunted Ron Weasley with visions of his deepest fears and even attempted to strangle Harry Potter.
A Horcrux leaves traces of Dark magic even when it is destroyed - this gives the person who touches the Horcrux visions of associated events and other related Horcruxes. When Harry Potter touched Marvolo Gaunt's Ring (one of Voldemort's Horcruxes), he experienced visions including Tom Riddle screaming in agony (possibly due to the method of ripping his soul).
A person who is a Horcrux also seems to possess some of the creator's abilities, such as Harry Potter being able to use Parseltongue which is one of Voldemort's inherited abilities. It also creates a mental link between the two the strength of which seems to depend upon the strength of the creator. For example:
- when Voldemort was weak and only in a spiritual form, Harry could only sense his presence when he was close by and feel his anger, but after he returned to somewhat of a body, this expanded a bit into the occasional dream vision of things happening with Voldemort. After Voldemort returned to full power, this link expanded so that Harry got full visions in his dreams of what Voldemort was dwelling upon, but the link can also be two-way and Voldemort was able to use it and Legilimency to implant a false vision in Harry's mind. The only way to sever the link completely and remove the abilities the Horcrux gives is to destroy the Horcrux itself.
To create a Horcrux is to divide one's soul — the "essence of self" — and it is therefore in the creation of a Horcrux that one falls prey to Adalbert Waffling's first Fundamental Law of Magic, which essentially states that tampering with one's soul inevitably results in grave side effects.
One of these such side-effects is the "dehumanising" effect the mutilation of one's soul is said to have. The more Horcruxes one creates, the less human they become, both emotionally and physically; Tom Riddle was initially shown to be hollow-cheeked but otherwise normal, though ten years later his features look as if they have been burned and blurred, and his skin was extremely white. One can hence assume that during those ten years he had created more than one Horcrux that in turn wrought the physical changes in Voldemort over that timespan.
Of course, this initial consequence of dehumanisation has its own side effect; it logically follows that if one becomes dehumanised by Horcrux creation then they will take less stock of morality in general, increasing the likelihood that they will create another Horcrux, which would in turn make them less human and hence less moral, which further increases their likelihood of making more Horcruxes and so on. In other words, Horcrux creation may be thought of as a "slippery slope" or "downward spiral" until one reaches the limit, at which point no more Horcruxes may be made.
One should note that it is unclear whether the red eyes and slit-like nostrils that Voldemort had after he was reborn are caused by having more Horcruxes than he did than when he applied for the Defence Against the Dark Arts post a second time, or whether they are characteristics of a person who has been resurrected with the help of serpents (who continued to play key roles in his revival until he finally died). It is probable that he performed these transformations prior to his resurrection as all of his Death Eaters seem to recognise him without question after Voldemort returned.
A third side effect of Horcrux creation is that the Master Soul itself becomes unstable (even with creating just one Horcrux). The precise dangers of this spiritual destabilization are not currently explained. For example, the creation of Lord Voldemort's seventh "Horcrux" - Harry Potter - is known to be the direct result of this as when Voldemort was hit by the back-fired Killing Curse at his parent's home in Godric's Hollow it caused his soul to split, with one fragment remaining in him and the other displaced part immediately seeking out the only other living thing in the room and latching onto it - Harry Potter.
However, one should note that although this parasitic fragment of Voldemort's soul attached to Harry's has been mistaken for a Horcrux it has been confirmed that in actuality it does not truly constitute one, since it was not created intentionally. Likewise, not all of the known parts of the Horcrux creation process were correctly carried out for it. Voldemort had just committed 2 murders (Harry's parents) so that may have been adequate for that requirement. In this state, Harry Potter may be more accurately described as a "proto-Horcrux", though for simplicity he may be termed a Horcrux regardless.
The final known side-effect of Horcrux creation is the inability to move on from Limbo after death. The more Horcrux' one makes, the more mangled ones soul becomes. Had they made several Horcrux' before their final death over all, their broken and mangled soul would be forced to exist in the stunted form of a small flayed and mutilated creature, unable to return to the land of the living, unable to become a ghost, and unable to go to the land of the dead because their soul was maimed and unwhole. It is unknown if this was a standard fate meted out for all Horcrux creators, or if it is unique to those who create several Horcruxes. Regardless, reconciliation cannot occur after death, as the soul's state at death remains forever, so the greatest of all consequences incurred by Horcrux creation may be the possibility of eternal limbo of the soul.
Herpo the FoulEdit
Herpo the Foul created the first Horcrux. Wether it still exists or was destroyed is unknown. Wether it had or has any protective spells on it is also unknown.
Voldemort (known originally as Tom Riddle), was the first to create more than one Horcux successfully, creating seven. These including his diary, a ring, a locket, a cup, a diadem, Harry Potter and his pet snake Nigini.