Immortal

Immortals are a species of supernatural beings that are truly immortal and cannot be killed by any weapon.

Immortals can be considered as the template for The Original Vampires and, in turn, all vampires. However, immortals differ to vampires in many different ways, and vice versa. The biggest of those differences being that they are still alive, rather than being undead like vampires, who must die after ingesting vampire blood so their bodies can be magically reanimated. They also do not possess superhuman physical powers to the same level as vampires; however, they do possess far superior range of psychic abilities than vampires.

History
It is currently unknown how immortals were created.

Nature
Immortals appear to have a physical form completely identical to that of a human, and do not have another form in addition to their human aspects, unlike their vampire cousins, who have a "true face" that causes the sclera of their eyes and the blood vessels surrounding them to swell and darken with blood.

Immortals, like vampires, require blood to live and maintain their supernatural abilities. However, unlike vampires, they have no fangs.

Powers and abilities
Immortals possess supernatural physical and psychic abilities. Although they are the first vampiric lifeforms to exist, their physical abilities e.g. their strength and speed etc. pale in comparison to that of vampires created from Esther's ritual, and do not increase over time. Their psychic powers however, are far more superior and the strongest seen thus far, having grow stronger with human blood and by simply honing them with intensive practice over time. - Voice Mimicry: When they use their illusions to appear as someone else, immortals are able to change their voice to whatever they want, using their voice in addition to their appearance to trick their victims into believing that they are truly who they are pretending to be.
 * Immortality: Immortals possess an infinite life span and are thus, immune to aging, all known diseases and illnesses and death by any conventional means. Unlike all other known semi-immortal beings like Vampires and Original Vampires, immortals are truly and unconditionally immortal and can't be killed by any means.
 * Advanced Healing Factor: Immortals are able to regenerate from any damage sustained on their bodies as a result of their unconditional immortality. Their bones snap back into place after being broken, and they have been seen to fully recover from gunshots, stab wounds, snapped necks, and torso impalement.
 * Advanced Immunity: Immortals possess a caliber of immortality that grants them immunity to all weaknesses. They're immune to wooden weapons, sunlight, vervain, werewolf bites, decapitation, heart extraction or fire and are able to walk freely into a home without being invited by the owner first. Their bodies are completely indestructible.
 * Psychic Powers: Immortals possess various advanced psychic abilities which they can develop to affect any species such as humans, witches, Original vampires, vampires, werewolves and hybrids, even at vast distances. In fact, immortals are the only known species who have abilities powerful enough to incapacitate or compel Original vampires. After intensive practice and consumption of exceptional amounts of blood, immortals can even affect multiple targets with their psychic abilities.
 * Telepathy: Immortals have the ability enter into the minds of another to read their thoughts and access their memories just by being in the same vicinity as them. This ability can also have its drawbacks if the user accidentally reveals information that they are not supposed to know, which can blow their cover if they are trying to appear as someone else.
 * Illusions: Immortals have the power to create powerful illusions. They are able to use these illusions on anyone they desire, no matter how powerful. The ability to cause illusions also allows a form of shapeshifting, since they can cause beings to believe that they are seeing the Immortal in the form of another. They can be used on multiple people in multiple locations simultaneously. They can keep themselves at a physically safe distance while casting illusions. The illusions have been proven sufficient against many vampires capable of brute force.

- Psychic Pain Infliction: Similar to witches with their pain infliction spells, immortals are able to inflict illusory psychic pain on their victims.
 * Advanced Mind Compulsion: Immortals can control thoughts, plague dreams, and erase memories of humans and supernatural creatures alike. They do not need eye contact, and can affect extremely powerful supernatural beings. Unlike vampires, vervain does not prevent an immortal from invading a victims mind. They are even able to control entire crowds from a distance with relative ease after feeding on a large enough quantity of blood. Immortals are the only known beings who can compel an Original vampire or hybrid.
 * Enhanced Strength: Immortals have greater than average strength that makes them stronger than most humans, enhancing their strength to more or less, so their strength can vary on how much blood is in their system. However, their strength is inferior to that of regular vampires.
 * Enhanced Speed: Immortals possess enhanced speed which allows them to move faster than humans.  However, like with their strength, immortal possess inferior speed to that of vampires.
 * Enhanced Reflexes: Immortals possess enhanced reflexes which allows them to unconsciously react faster than humans to stimulus.
 * Super Durability: Immortals are indestructible, they are highly resistant to pain and can take a great amount of damage without succumbing to physical injury.
 * Enhanced Senses: Immortals have a keen sense of hearing, sight, smell, taste, touch, and perception that exceed those of humans although, the degree of which is still unknown.
 * Shapeshifting

Weaknesses
Despite being truly immortal and being incredibly powerful in their own right, immortals do possess some weaknesses, as Nature requires a balance and will not allow any living thing to be truly invulnerable.
 * Broken Neck: Breaking an immortal's neck will result in unconsciousness of said immortal until their regenerative healing ability kicks in and repairs the damage to the spinal cord.
 * The Cure: If an immortal takes the cure, they will become human and mortal again.
 * Desiccation: Immortals who abstain from blood for extended amounts of time will eventually desiccate into mummification. Desiccation can also be caused by magic in order to incapacitate the immortal in question.
 * Magic: Immortals are susceptible to the powers of witchcraft.
 * Physical Trauma: Minor physical injuries such as gunshots, stab wounds and broken bones will cause an immortal pain and also slow them down. However, this is momentary as they will heal completely within seconds, so long as they have fed recently. It seems physical trauma can hurt them anywhere on the body (ex-eye gauging, drowning).

Trivia

 * Vampires can turn humans into their kind, but it is unknown if Immortals can do the same.
 * Immortals are mentally the most powerful creatures on both shows.
 * Silas mentions to Stefan that he has never once died and thus didn't know what dying feels like, confirming that immortals are actually not undead.