Alastair

Alastair was a powerful, white-eyed demon who was Hell's grand torturer, and Meg apprenticed under him in the field of torture. He was able to travel from Hell and Earth with incredible ease, something he shares with Azazel. His stature to Lilith is vague, but the way he grudgingly followed her orders indicates that she at the very least out-ranked him. Dean Winchester first encountered Alastair in Hell, and he was the one in charge of torturing him on orders directly from Lilith, as to break the first seal.

During the 40 years (or 4 months in Earth time) that Dean was in Hell, each day Alastair would ask Dean if he wanted to trade his place for another soul. For 30 years, he refused and, each day, was chopped and killed and then placed back together, only for the cycle to continue. He couldn't bear the pain much longer and, for 10 years, tortured souls. This makes Alastair directly responsible for triggering the Apocalypse. He was eventually killed by Sam Winchester with his psychic powers.

Early life
Nothing is known about Alastair's life as a human, nor is it known how he became Hell's Grand Torturer. What is known is that while in Hell, he gained a reputation for being cruel and sadistic - a reputation which made even other demons fear him. He also became one of the few demons who actually enjoyed life in Hell more than life on Earth. At some point in his career, he trained Azazel's "daughter" Meg in the art of torture.

Alastair last walked the Earth in Nazi-occupied Poland around 1943 during World War II. Given Alastair's personality, he probably possessed a Nazi scientist and tortured Holocaust victims.

Some time during John Winchester's imprisonment in Hell, Alastair took command in attempting to break him in the name of the first seal; however, John endured the torture for a century without breaking before being freed during the events of All Hell Breaks Loose - Part 2. At the end of No Rest for the Wicked he encountered Dean in Hell, and resumed the same duty as before.

Pre-Season 4
In Hell, Alastair was assigned to torture Dean. He did so for 40 years, finally breaking him after 30. In doing so, the first of the 66 Seals was broken, setting the Apocalypse into motion.

Season 4
Alastair resurfaces on Earth to try to capture Anna Milton and use her gift for their gain. During this time, he re-encountered his favorite student Dean who remembered him from Hell. Although his initial attempt was unsuccessful, he manages to get a hold of Ruby's magical knife. Later, he returns and strikes a deal with Ruby, who promises Anna for the safety of the Winchesters and herself. Alastair, after torturing Ruby, accepts. Unknowingly, however, he falls into a trap set by the Winchesters and is confronted by two angels, Castiel and Uriel. He and his demonic minions get into a fight with the angels, although his minions are easily killed, Alastair proves to be a stronger opponent, and casually knocks about Castiel, and during the battle, Anna regains her grace and lets loose of a blast of light that disintegrates Alastair's vessel.

He returned a short while later, possessing a new body. He was behind the abduction of a reaper in a small town. He encountered Sam and Dean and fought them, before escaping when Sam revealed that he's immune to his power. He gained a new vessel soon after and abducted a second reaper named Tessa who Dean knew. He planned to kill the two reapers on the night of the solstice moon to break another of the 66 Seals that needed to break in order to free Lucifer. Sam and Dean, in their astral forms, used their new ghost abilities to fight Alastair; however, he was able to trap them in an iron chain, mocking them about how they often did the same to spirits. However, through a combination of their new abilities, they managed to bring the chandelier down on him, breaking the ring and freeing Tessa. He failed, only being able to kill one reaper, and was captured by the angels.

After seven angels were killed, Castiel recruited Dean to torture information out of Alastair. Alastair simply mocked the fact that his former protégé would be the one to try and break him. Alastair revealed that the first seal was broken when Dean gave in and began torturing souls in Hell. This explained why the angels had rescued Dean from Hell. With some help from Uriel, Alastair managed to break free from the Devils Trap he was bound in through water dripping from a pipe and washing away a portion of the symbol.

"You should talk to your plumber about the pipes"

-- Alastair to Dean before disfiguring his face with a single punch.

He quickly beat up Dean and nearly banished Castiel to Heaven until Sam arrived and pinned Alastair against a wall using telekinesis. He tortured Alastair until the demon revealed that the demons were not behind the angel killings. Alastair then challenged Sam to exorcise him, but Sam, now being more advanced with his powers, simply used his abilities to kill Alastair in a similar fashion to what the Colt or Ruby's knife would do. It was later shown that Uriel  was behind the angel killings.

Alastair appears again as a hallucination to Sam during the latter's detoxing of demon blood. In this hallucination, Alastair is torturing Sam.

Personality
"When we win, when we bring on the Apocalypse and burn this Earth down, we'll owe it all to you, Dean Winchester. Believe me, son, I wouldn't lie about this. It's kind of a religious sort of thing with me."

- Alastair to Dean Winchester

Alastair was cruel, even for a demon, especially in his sadism. The more pain he could deliver the happier he was, but not just physical pain--he was also effective in mental torture and stress. He viewed torture as an exquisite art and enjoyed being patient and relishing the moments where he tortured his victims. He also criticized Ruby, stating that young demons were always so impatient and willing to run into things. While torturing his victims, Alastair often talks to his victims in a calm, polite manner as they scream in pain. Even when he is being tortured by Dean, he retains this trait, spending the whole time offering Dean advice, commenting on Dean's technique or reminiscing about the days in Hell when he apprenticed Dean in the art of torture.

As well as enjoying giving pain, Alastair enjoyed receiving it, which displayed his masochism. He seemed to enjoy being tortured almost as much as he enjoyed torturing others, mostly because he relished in watching his enemies fail to get anything out of him and enjoyed observing their frustration. Despite being "a black belt in torture" himself, even he had a threshold for the pain he could withstand. For these reasons, he was the only demon, who didn't just like Hell, but liked it more than Earth, dismissing the Earth as an "arctic craphole" and several times expressing the wish to return down under, feeling completely at home when among the gruesome horrors in Hell. Ultimately, Alastair could be seen as more of an artist than a politician who cares more about carving up people than he cares about the Apocalypse, only tolerating being sent to Earth because he gets a chance to aggravate the angels and because he is ordered to. He even explicitly states that he wishes to finish his duties on Earth as quickly as possible so he could return to his studies. As "the Grand Inquisitor Downstairs", Alastair is feared by almost all who know him, to the extent where demons fear him more than they fear angels. He did, however, seem to respect Lilith and shared her desire to bring the Apocalypse and watch the world burn. As she is his superior, he loyally obeys her orders and would never disobey her, even if it means he has to leave Hell to complete his mission.

He also held contempt for angels, referring to them as "sanctimonious, fanatical pricks" and compares them to cockroaches, and enjoyed hurting them, even more than he enjoyed humans, souls and demons. He wished he knew how to kill them, rather than simply being able to send them back to Heaven. He was extremely confident and one of the few demons who did not flee in the presence of an angel, stating that he'd "take his chances" when challenged by two angels.

Alastair had a twisted sense of humor, and never missed a chance to exploit something he considered funny or ironic. He believed that the fact his previous host's wife was still looking for him was "hilarious". Alastair also liked to break his enemies spirit such as when he told Dean that his father lasted 100 years on his rack without breaking while Dean broke in just 30 years and when he reveals to Dean that he was responsible for the destruction of the first seal. Despite being completely evil, Alastair did apparently form a twisted mentor-student bond with those he took under his wing in the field of torture, such as Dean.

Powers and Abilities
Alastair was one of the most powerful demons to appear on the show. Even in a weakened state from the injuries he sustained from the prolonged torture at Dean's hands, he could still overpower a common angel such as Castiel. Alastair belongs to the highest hierarchy of Hell, although he was still subservient to Lilith. His arrival caused a church statue of the Virgin Mary to weep blood in "I Know What You Did Last Summer".


 * Immunity - Alastair could not be killed by smiting from a lower-level angel. He was immune to iron and able to walk on holy ground. Sam's demonic powers initially did not work on him, although Ruby later explained that this was because Sam had stopped drinking Demon Blood; once Sam began drinking blood again, Alastair's powers stopped working on him and Alastair began taking precautions to ensure that Sam would not use his powers on him, implying that Alastair lost his immunity to Sam's powers (which was later proven true in "On The Head Of A Pin"). Alastair was also extremely resistant to Ruby's Knife as it only caused him mild pain rather than the agony most Demons feel, and it was not deadly to him when stabbed in the stomach and upper chest.
 * Invulnerability - Alastair withstood would-be fatal injuries such as numerous stabbings and prolonged torture with little reaction.
 * Telekinesis - Alastair had the ability to move objects with his mind. He used hand gestures to drag and throw people over large distances without physically touching them. During his first appearance, he also blasted apart a door without noticeable use of gestures.
 * Torturing - Alastair was an expert in how to torture humans and demons alike. His skills at torture was such that even other demons feared him, nicknaming him "Picasso with a razor." Because of his prowess, Alastair was often issued special assignments in torture, including breaking John and Dean's souls in Hell and interrogating Anna.
 * Teleportation - Alastair could teleport from one place to another, including travel between Hell and Earth. He appeared directly behind Ruby in "Heaven and Hell", despite there having been nobody there even seconds before that. He did the same to Dean in "Death Takes A Holiday" and "On The Head Of A Pin"; in the latter episode, he even slipped out of a number of chains binding him without making them make noise from his escape.
 * Immortality - Alastair could potentially live forever. Although his exact age was not revealed, he considered Ruby, who was over seven hundred years old, to be a young demon.
 * Knowledge of magic - Alastair knew an exorcism which expelled angels from their vessels; he tried to use this exorcism on Castiel in "Heaven and Hell" and again in "On the Head of a Pin", but was interrupted both times. He also knew Enochian sigils which warded buildings against angels, and a spell which incapacitated reapers. Additionally, he had knowledge of the 66 Seals and how to break them.
 * Biokinesis - Alastair directed a psychic attack on Sam and Dean simultaneously in "Heaven and Hell" by raising his hand at them; causing them to grip their chests and fall down, implying that he was attacking their hearts, or lungs.
 * Possession - Alastair used a pediatrician as his vessel in "I Know What You Did Last Summer" and "Heaven and Hell". When Anna regained her grace, the light she emitted destroyed the pediatrician, forcing the demon to claim a new vessel when he returned to Earth in "Death Takes a Holiday". He soon fled this vessel and possessed a third man, whom he continued to possess until they were both killed in "On the Head of a Pin".
 * Flight - In his disembodied smoke form, Alastair could fly.
 * Supernatural Perception - Alastair could perceive beings that are invisible to humans such as ghosts, demons and reapers.
 * Super stamina - Alastair had an incredibly high pain threshold, withstanding hours of extreme torture from Castiel, Uriel, and later Dean (his own pupil in torturing) without giving up any information. When he got free, he showed no signs of weakness or exhaustion despite multiple injuries to his vessel.
 * Super strength - Alastair was an incredibly strong demon, able to overpower both common angels and demons with relative ease. Alastair lifted and strangled Dean with one hand without any signs of strain. He also lifted Castiel and placed him on a hook while they were both in vessels despite being weakened by hours of torture. Even without a vessel, he was strong enough to overpower and capture a Reaper.

Weaknesses
Alastair had few true weaknesses. He was one of the strongest and most durable demons ever to exist.

Harming, Misleading or Trapping

 * Devil's Trap - He could be trapped by a devil's trap.
 * Heavenly Host - Multiple angels acting collectively could capture Alastair.
 * Holy water - Holy water could cause him pain.
 * Salt - Salt could cause him pain.
 * Demon-killing knife - This knife could injure Alastair.

Killing

 * Special Children - Alastair was vulnerable to a special child's powers and he was killed by one.

Appearances

 * Season 4
 * I Know What You Did Last Summer
 * Heaven and Hell
 * Death Takes a Holiday
 * On the Head of a Pin
 * When the Levee Breaks (Appears as hallucination)
 * Lucifer Rising (Mentioned only)


 * Season 6
 * Caged Heat (Mentioned only)
 * The Man Who Would Be King (Mentioned only)