Twelfth Doctor

The Twelfth Doctor emerged from his predecessor's explosive regeneration on Trenzalore, being the product of "regeneration number thirteen." He was the first incarnation of the Doctor's second regeneration cycle, which had been bestowed upon him by the Time Lords.

Assured of the survival of Gallifrey, he was no longer chained down by his guilt. A darker character, he questioned his own goodness. Although this incarnation was no stranger to kindness and humor, he often dispensed with niceties in a tense situation, becoming cold and calculative in critical moments that required sound judgment and the occasional application of sharp practice.

However, because of his detachment from emotions, he could come off as unpleasant, fearsome, and ruthless. These qualities often terrified those who were around him, even his companions. He became harder to trust, and acknowledged his shift toward negative personality traits, feeling incensed and fearful at what he was changing into.



A chaotic beginning
After fighting in the Siege of Trenzalore for 900 years, (PROSE: Tales of Trenzalore: The Eleventh Doctor's Last Stand) the Eleventh Doctor, facing extermination by the Daleks in his old age, was ready to accept that he had reached the end of his life. Clara Oswald appealed to the Time Lords to intervene, and he was granted a new regenerative cycle. After using his regenerative energy to destroy the attacking Daleks and their mother ship, the Eleventh Doctor returned to the TARDIS, where he completed his regeneration into the Twelfth. (TV: The Time of the Doctor)

Crash-landing on pre-historic Earth, the TARDIS was chased and subsequently swallowed by a female Tyrannosaur; when the Doctor brought the TARDIS to 1890s London, this dinosaur was accidentally brought along with it.

In London, the Doctor was reunited with the Paternoster Gang, and witnessed the apparent spontaneous combustion of the dinosaur. Though still suffering from partial amnesia and occasional delirium as after-effects of his regeneration, he learned Clockwork Droids had been harvesting humans to repair themselves. Their leader, the Half-Face Man, sought to reach the Promised Land. The Doctor confronted the Half-Face Man, who fell from his escape pod and was impaled on Big Ben.

The Doctor briefly left Clara behind in Victorian London, during which time he redecorated the TARDIS console room and settled on a new outfit. Attempting to return her home to London in the 21st century, the Doctor ended up in Glasgow by mistake. She was initially not sure if she could continue travelling with this changed Doctor. However, they decided to go out for coffee after Clara received a phone call (via the TARDIS) from the Eleventh Doctor, who encouraged her to help his successor, knowing all too well how traumatic a regeneration was. (TV: Deep Breath)

Am I a good man?
Having rescued Journey Blue and found a damaged Dalek, the Doctor returned to Earth to collect Clara and took her back to the Aristotle where they were miniaturised and put inside the Dalek to discover if it could be "good" - the creature professing that it wanted to exterminate others of its kind.

The Doctor nicknamed it "Rusty" and learned that the Dalek had decided that life could not be stopped when it saw star being born, making its efforts to destroy other life fruitless. The Doctor repaired a radiation leak with Rusty, but this resulted in the malfunction being reversed, with Rusty's destructive nature reasserting itself. It went on a killing spree. After being lectured by Clara for his apathy, the Doctor realised that "a good Dalek" was possible because the Dalek still had memory of the star, but it was suppressed by the cortex vaults.

The Doctor linked his mind with Rusty, who saw the Time Lord's hatred of the Daleks, leading it destroy those of its kind that had responded to his distress beacon. Rusty then left to continue its crusade against the Daleks. The Doctor declined Journey's request to join the TARDIS crew as she was a soldier. (TV: Into the Dalek)

New adventures with Clara
Spending some more time on his own, the Doctor became alerted to a creature that disguised itself as a motorway to consume planets into other dimensions. Summoning Clara to assist him, the Doctor was surprised when the creature disappeared, unaware that Clara had tricked the creature into consuming itself. (COMIC: Road Rage)

Deciding to give Clara the choice of their next destination, the Doctor took her to Sherwood Forest to meet Robin Hood, though the Doctor was sceptical of Robin's actual existence. He was proven wrong immediately on arrival when Robin shot his TARDIS with an arrow; however, he remained determined to prove Robin Hood and his Merry Men were a fake.

After participating in an archery contest for a golden arrow, the Doctor, Clara and Robin were caught by the Sheriff of Nottingham, who had allied with alien robots disguised as his knights. Escaping, the Doctor found out that the robots were trying to reach the Promised Land, but lacked sufficient gold to repair their engine. Believing Robin was also a robot, the Doctor was captured by the Sheriff as Clara and Robin escaped through a window. Leading a revolution in the Sheriff's dungeon, the Doctor was informed by the Sheriff that Robin Hood was not a robot, just as Robin came to his rescue and defeated the Sheriff. Assisting Robin with Clara's help, the Doctor helped launch the golden arrow into the ship to allow it to escape velocity and explode harmlessly in space.

Robin, having learned about the Doctor's story from Clara, noted that the two of them were not so different from each other. Both of them were people born into status and privilege, giving up both to live the life of an adventurer in order to fight injustice. (TV: Robot of Sherwood)

The Doctor and Clara used a goo bomb to foil the Sibro's attempt to weaponise a Conlanian clock tower, (COMIC: Chime Time) orchestrated a ceasefire in a war between anthropomorphic cats and dogs by allying them against an army of alien fleas that planned to attack every planet in the universe, (COMIC: Once Bitten) and helped the World Brain find a new way of life after crash landing on it's factory planet. (COMIC: Crash Landing)

Visiting the planet Hoopoe, the Doctor acted as Clara's lawyer after she was arrested for walking on the ground by the Court of Birds. His attempt to convince them she and him weren't cats backfired when the owls accused them of being mice, but the Doctor had foreseen this and had recruited the native cats to attack the owls with makeshifts wings, but ensured that the wings were too difficult to use properly, rendering them useless in the cats' pursuit of the owls. As he left with Clara in the TARDIS, the Doctor rewarded the cats with a box of canned tuna. (COMIC: The Court of Birds)

During one of Clara's breaks from the TARDIS, the Doctor became obsessed with the idea that a creature designed to hide was following him around and that everyone was similarly being followed. Visiting Clara for help in finding the hiders, by using the TARDIS telepathic circuits to pilot into her past. However, Clara got distracted by a phone call from Danny Pink and piloted them into his past instead, back when Danny was called Rupert. Finding a figure under Rupert's bed sheet, the Doctor had Clara and Rupert turn their backs to allow the being to walk out the room unobserved, leaving them unsure if it really was a creature or just another child playing a trick on Rupert.

Returning Clara to her date with the adult Danny Pink, the Doctor continued to follow his theory by trying to use a trace of Clara left in the telepathic circuits, ending up at the end of the universe where a time traveller named Colonel Orson Pink had been trapped for six months. Intrigued by how following Clara's timeline led him to Orson, the Doctor returned for Clara and had them wait at the end of the universe for the night, believing it to be the perfect time to find out if the hiders were real. Finding a chance to confront the creature outside the ship, the Doctor sent Clara into the TARDIS and seemed to get a look at what he's been chasing before the atmospheric shell broke and Orson had to rescue him. As the Doctor was knocked out, and the TARDIS seemed to be under attack, Clara used the telepathic circuits to fly the TARDIS away.

Waking up to find Clara gone, the Doctor called out to her and inadvertently alerted his young self to Clara's presence. Before he could investigate, Clara re-entered the TARDIS and made him promise to leave and not find out where they had landed. Afterwards, the Doctor returned Orson and Clara to their own times and, satisfied by what he had learned, underlined the word "Listen" that the creature had written on his chalkboard. (TV: Listen)

Returning to pick up Clara, and persuade her to away from a date with Danny Pink in favour of other travel destinations, the Doctor received a call from Madame Karabraxos, who requested he free the Teller and its mate from the Bank of Karabraxos, as he had done on the day she met him. Realising the ramifications of this request, the Doctor build up the identity of "the Architect", using this identity to stage a bank heist for him to commit, with the assistance of Clara, an augmented human named Psi, and a shape shifting mutant human named Saibra.

Using memory worms to erase the plan from their minds and prevent the Teller from alerting the young Karabraxos, the Doctor and Clara found themselves already in the Bank with their accomplices, their last memory being the TARDIS phone ringing.

Receiving instructions from the Architect on their location, objective, and the Bank's security system, the team infiltrated the Bank. Entering a safety deposit box, Team Not Dead - the Doctor's name for the assembled team - set of a dimensional shift bomb into a service corridor, where the team found a briefcase containing six teleporters disguised as atomic shredders.

Seemingly losing Saibra and Psi to the shredders when the Teller locked onto them, the Doctor figured out that time travel was involved with the heist plan when a perfectly-timed solar storm unlocked the Bank's vault. Retrieving what the Architect had promised Psi and Saibra as payment, the Doctor and Clara were caught by the Teller and delivered to the bank manager, Ms. Delphox. After Delphox left them to be executed, the Doctor and Clara were saved by Psi and Saibra, who revealed the true nature of the "shredders".

Venturing into the Bank's private vault to find his and Clara's reward, the Doctor instead found Director Karabraxos, and discovered that Delphox, as well as a majority of the bank's staff, was an exact clone of Karabraxos. Seeing Karabraxos' hatred of her own clones caused the Doctor to have an epiphany on the identity of the Architect, and he gave his phone number to Karabraxos as she fled from the solar storm about to hit the Bank. Subjecting himself to the Teller's powers, the Doctor regained his lost memories and realised the true objective of the bank heist. Freeing the Teller and its mate to a place to live in solitude, the Doctor then parted ways with Psi and Saibra, giving them their rewards, and returned Clara home for her date. (TV: Time Heist)

The Doctor and Clara were left to the mercy of sand piranhas while chained to posts on a Desert planet, rendezvoused with fish people and outran soldiers to escape in the TARDIS. (TV: The Caretaker)

The Doctor went looking for Clara at Coal Hill, but it ended up being another planet and not Coal Hill at all. To rescue Clara, Jeff Delobel and Earth from a potential alien invasion, he told the aliens a story of Earth's guardian (being himself), which scared them into proceeding into the invasion. (COMIC: The Monsters of Coal Hill School)

The duo were also stranded and about to be turned into toast by an Aaraanandal slime beast, before being saved by Simon (a 22nd century alien invasion survivor, left behind during evacuation), who used the stranded TARDIS as a base, and accidentally used the telepathic circuits, landing around the Doctor and Clara. The Doctor then took Simon to his mum and dad. (PROSE: When the Wolves Came)

Clara woke up, behind late for work, so she phoned the Doctor to land there on time. The Doctor ended up being side tracked, and took them to a level 1 planet called Eden 2. In the end, the planet was frozen by a species called the Vladlack, but was found out that the planet was fighting back. It was revealed that the planet was a trap, to lure in and arrest invaders of planets and sentenced the Vladlack to 1000 hard labour in their prison planet. The Doctor stopped that from happening, because even guilty species must go on trial, and innocents could get arrested too. He then took Clara to school, half an hour earlier. (COMIC: Freeze)

Meeting Danny and Courtney
Discovering a Skovox Blitzer near Coal Hill School, the Doctor went in deep cover as the school's temporary caretaker to dispatch of the killer robot, much to Clara's dismay.

Initially planning on using chronodyne generators to send the Blitzer into the future, the Doctor's plan was accidentally foiled by Danny Pink. After Clara introduced the two, the Doctor changed his plan to using a communication device to make the Blitzer think the Doctor was its superior.

After successfully commanding the Blitzer to deactivate, the Doctor took into space and ejected it from the TARDIS, taking Courtney Woods with him after she discovered his identity, deciding that there was no harm in having Courtney tag along as a travelling companion, (TV: The Caretaker) but didn't see anything special in her, which hurt Courtney's feelings. (TV: Kill the Moon)

Fallout with Clara
At Clara's urging, the Doctor took her and Courtney to the Moon in 2049, so that Courtney could be the first girl on the Moon. Landing in a recycled space shuttle heading for the moon instead, the Doctor was informed by Captain Lundvik that the moon had gained more weight and that they were going to use nuclear bombs to dispose of the additional weight.

Investigating a disused mining base from a previous mission, the Doctor, his companions and the astronauts found corpses preserved in webs and research that suggested that the moon was disintegrating. Soon after, the group was attacked by a spider creature, which Courtney killed with washing up equipment, but not before Lundvik's crew were killed.

Taking a scared Courtney back to the TARDIS, the Doctor voiced his uncertainty of the Moon's fate to Clara, calling a "gray area" in time. Exploring the moon's surface for the reason behind the deterioration, the Doctor, Clara and Lundvik discovered a horde of spider germs beneath the Moon's surface, as well as amniotic fluid, prompting the Doctor to investigate beneath the Moon for answers.

Scanning the Moon's core, the Doctor discovered that the Moon was, in fact, an egg for an ancient creature that was hatching. Reuniting with Clara and Lundvik after the shuttle and the TARDIS fell into a canyon, the Doctor informed them of his discovery after establishing contact with Courtney's phone. While Clara and Lundvik argued about killing the creature for the sake of the Earth, the Doctor had Courtney bring the TARDIS to him via DVD, deciding that it was not his place to decide the Moon's future, and left in his TARDIS for Clara, Lundvik and Courtney to decide on behalf of humankind.

After Clara chose to spare the creature, despite humanity voting for it's death, the Doctor returned for the three women, taking them to a beach on Earth to see the creature hatch and the Moon harmlessly disintegrate in Earth's atmosphere. Confirming that the sight of the moon hatching kick started the humans pioneering into space, and seeing the creature hatch a new egg with same mass as the old Moon, the Doctor returned Courtney and Clara to Coal Hill School.

However, Clara, angered by the position the Doctor had put her in, asked the Doctor if he had known the egg was harmless, which the Doctor confirmed as true. Tired of the Doctor's apathy, Clara argued with the Doctor about how he had almost caused her to kill an unborn creature. He defended that he was helping the human race by not playing a part in this choice. However, Clara had been deeply hurt by the Doctor's constantly patronising attitude toward humanity, and now that he had demonstrated it with her, Clara felt reduced to the likes of an idiot in the Doctor's eyes. With tears rolling down her face, she told him to leave and not return for her. The Doctor was left stunned by her reaction and immediately took off. (TV: Kill the Moon)

Clara rejoins
Reuniting with Clara for a farewell trip, the Doctor took her to a space-bound Orient Express. He later confessed to her that he had chosen the destination with an inkling that something exciting would happen after having been lured with phone calls, mysterious summons and free train tickets.

After discovering the death of an elderly passenger, and urging himself to investigate, the Doctor went to the engine room to examine the dead passenger's Excelsior Life Extender, meeting Chief Engineer Perkins in the process, and learned the rumor of the Foretold. Seeking advice from Emile Moorhouse, a fellow passenger who was a Professor of Alien Mythology, the Doctor soon discovered a second death had occurred in the kitchen.

Confronting Captain Quell with his theory, but getting ignored, the Doctor joined Perkins and Moorhouse in the engine room to research the deaths. Calling Clara to update her, the Doctor discovered that she and Maisie Pitt were trapped in a storage cart with a sarcophagus. Fearing that Clara was tapped with the Foretold, the Doctor tried to rewire the door open, only to find the sarcophagus empty, and himself under arrest by the Captain for being a stowaway.

However, after witnessing a third death firsthand, Quell realised that the Doctor was right and allied with him, just as the Doctor deduced the true nature of the Orient Express; the passengers were all experts and scientists in specific fields of study, gathered there to study the Foretold. With a lab revealed and the hologram passengers disappearing, the train's computer, Gus, gave the scientists the necessary instructions and equipment. Losing Moorhouse to the Foretold, the Doctor and Perkins figured out that the Foretold was targeting the weaker passengers after looking at the medical history of the previous victims, just as Quell was killed by the creature, as he had post-traumatic stress, but not before he gave the Doctor the necessary description to defeat the Foretold.

Realising that Maisie was next due to her breakdowns, the Doctor told a reluctant Clara to bring Maisie to the lab. Arriving there, the Foretold appeared to Maisie, but the Doctor saved her by implanted a replica of her grief into his head, confusing the Foretold into thinking the Doctor was Maisie. Deducing that the Foretold was an ancient soldier augmented with technology, the Doctor surrendered, and, after a final salute, the ancient soldier crumpled top dust, with only the technology that kept him alive remaining.

Demanding answers about the situation, Gus instead released the air out of the cabin, the Doctor beamed all the passengers as they began to fall unconscious into the TARDIS, and tired to hack Gus to find out who had created him, but this trigged a security measure, causing the train to self-destruct. Dropped everyone but Clara and Perkin off at the nearest civilised planet, the Doctor waited for Clara to awaken on a beach before explaining everything.

Back in the TARDIS, the Doctor invited Perkins to travel with him, but Perkins politely declined and he and the Doctor bade each other goodbye. Reflecting on a conversation she had with Maisie, Clara, having forgiven the Doctor, decided to continue travelling with him, telling the Doctor that her leaving was all Danny's idea. (TV: Mummy on the Orient Express)

The Doctor and Clara travelled to the planet Isen VI, so that Clara could practice skiing for a school trip. Although the Doctor remembered it as a very cold and snowy planet, it had been converted to a warm and tropical paradise. After rescuing Clara from monkey-like creatures, the Doctor found an artificial leaf, which led to him and Clara being accused of trespassing by the planet's owner, Kano Dollar. The Doctor found that as a result of the planet's manipulation a global cataclysm was imminent, but Dollar wouldn't listen. The Doctor and Clara rescued two workers from an underground earthquake with the TARDIS and moved to a cavern beneath the tower. The Doctor had discovered a Gallifreyan signal and wanted to investigate. They found a giant terraformer, which had fused with a ship underground. From the ship came a being called Hyperios, who announced the universe would fall. (COMIC: Terrorformer)

Undated events

 * The Twelfth Doctor joined his previous selves in helping place Gallifrey in a pocket universe at the end of the Last Great Time War. (TV: The Day of the Doctor)

Personality
A sarcastic man armed with a dry, acerbic wit and a brutal honesty, the Twelfth Doctor was dark and at times manipulative. In comparison to his predecessor, he described himself as having had "sophistication and timeless sartorial elegance" restored. (COMIC: Terrorformer) He was perfectly comfortable with placing his companions in danger if it meant appeasing his curiosity, often leaving them out of the details in his plans. However, if he believed the situation was too dangerous for them, the Doctor would send his companions to the safety of the TARDIS while staring down the threat alone. (TV: Deep Breath, Listen, COMIC: Chime Time)

Despite coming across as uncaring, he would fight to protect those in his care, and would react with devastation if harm befell them. Such was his reaction to the death of a female Tyrannosaurus rex that had been inadvertently dragged through time by the TARDIS. (TV: Deep Breath) However, for the most part, this Doctor was far more detached than his immediate predecessors and was occasionally callous, reacting with indifference during his first encounter with Journey Blue, who had just lost her brother, (TV: Into the Dalek) and laughing at Orson Pink's name, though he apologised for the latter. (TV: Listen) He also acted indifferent to the apparent death of Saibra, causing Psi to ask him if he called himself the Doctor due to professional detachment. (TV: Time Heist)

The Twelfth Doctor showed even less restraint than his predecessor, and would get frank and physical with his enemies. (TV: Deep Breath) However, he had a conflicted sense of morality and struggled with his inner darkness. While he sometimes voiced preconceptions about the Daleks or human nature, he often questioned his own judgement afterward. Indeed, behind this waspish exterior was a man who was extremely self-reflective, to the point where he questioned if he was still a good man.(TV: Deep Breath, Into the Dalek)

Though he retained a respect for humanity, the Twelfth Doctor would insult them for being slow minded and violent, dubbing Earth the "planet of the pudding-brains". (TV: Deep Breath) He expressed a strong dislike for soldiers, because of their hidebound nature, (TV: Into the Dalek) and was easily annoyed by swashbucklers who did not take things seriously. (TV: Robot of Sherwood) He also claimed to dislike karaoke, mime, babysitters, and bantering. (TV: Deep Breath, Into the Dalek, Robot of Sherwood)

Unlike his immediate predecessor, the twelfth incarnation was not a affectionate Doctor, failing to return Clara's hugs, or protesting against them, (TV: Deep Breath, Listen) and being momentarily dumbfounded when Maid Marian pecked him on the cheek in gratitude for saving her. (TV: Robot of Sherwood)

The Doctor informed Saibra that, despite how much he hated him, he had no intention on killing the Architect. (TV: Time Heist)

The Doctor acted like a pragmatist who would not hesitate to abandon someone whose fate was already sealed, (TV: Into the Dalek) nor mourn for an ally until his objective had been reached. (TV: Time Heist)

He would keep his companions in the dark if he knew there would be no danger to Earth or themselves, one major example of such behaviour was when the Doctor, along with Clara and her student Courtney visited the moon in the year 2049; the three of them along with a spacewoman called Lundvik discovered that the moon was actually an egg, which was at that moment getting ready to hatch and unleash a creature from within, which Ludvik thought would bring harm to Earth. When asked by Clara what they should do the Doctor claimed that it wasn't up to him to decide what to do with the creature inside the moon and left in the TARDIS, leaving his three companions to decide what to do on mankind's behalf, however he would later come back after Clara had made the right choice to let the creature live and told an emotional Clara much later on he knew it wouldn't have attacked Earth. This would lead to a divide between Clara and the Doctor, as Clara was disgusted with how the Doctor had known all along about the creature being harmless while she was left with the choice to either kill an unborn creature or let it live, with the Doctor arguing that he had actually helped save humanity by not assisting Clara, Courtney and Lundvik. (TV: Kill the Moon)

Despite the secrecy this Doctor, like his previous incarnation, relied on his companions to keep him from succumbing to his darker nature, but, unlike his predecessors, the Twelfth Doctor actively praised them for it, even claiming that Clara Oswald needed a "raise" for dealing with him. (TV: Into the Dalek)

By his own testament, the Twelfth Doctor did not suffer fools gladly, (PROSE: The Blood Cell) nor did he tolerate poor manners, even when held at gunpoint, and believed that one should make requests politely. (TV: Into the Dalek)

Having devoted countless centuries to combating them, this Doctor's hatred toward the Dalek species was rigid, with Clara describing it as "prejudice". He seemed conditioned to believe Daleks could not change and was closed-minded as he dealt with their presence. After his act of fixing a malfunctioning "good" Dalek caused it to revert to "evil", the Doctor was almost pleased that his belief of there being "no such thing as a good Dalek" was vindicated. This horrified Clara, who became angered to the point of slapping him.

His revulsion of the Daleks was so intense that when he entered Rusty's mind, intent on showing it the beauty of the universe, he ultimately exacerbated its homicidal nature. Instead of offering it a soul, the Doctor, through his sheer hatred for the Daleks, reconditioned Rusty into a merciless killer of its own kind. (TV: Into the Dalek)

This Doctor, as with previous incarnations, was also not above self-loathing. During his mission to the rob the Bank of Karabraxos, the Doctor realised he himself was his team's employer, "the Architect," due to the extent to which he hated him. He described the Architect (and by extension himself) as overbearing, manipulative and consciously aware of his own intelligence. (TV: Time Heist)

Additionally, he was at times critical of his previous incarnations' clothing. He opined that his fourth self's scarf "looked stupid" (TV: Deep Breath) and regarded his immediate predecessor's fondness for bow ties as "embarrassing." (TV: Time Heist) However, upon seeing Adrian, a teacher at Coal Hill School with a fashion sense reminiscent of his previous incarnation, complete with bow tie and hairstyle, he responded more favourably due to being under the mistaken impression that he was Clara's boyfriend. Arrogantly, he assumed that Clara was dating Adrian because of his uncanny resemblance to "a certain dashing young time traveller." (TV: The Caretaker)

Habits and quirks
Much like his seventh incarnation, the Twelfth Doctor spoke with a Scottish accent, although his was notably thicker. He took his new accent as an entitlement to complain about things. (TV: Deep Breath)

When proposing a theory, the Doctor would use words such as "question" or "proposition", and would begin his conclusion with "answer" or "conjecture". After working out the important questions in his head, he waited for others to come to the same conclusion, becoming increasingly annoyed with each wrong question they proposed. (TV: Deep Breath, Listen, Time Heist)

Like the Ninth Doctor labeling humanity as "stupid apes", the Twelfth Doctor would call them "pudding brains" when he found them slow-minded and stupid. (TV: Deep Breath, Robot of Sherwood )

When in a moment of realisation or thinking intensely, the Twelfth Doctor would often tell people to "shut up", regardless if anyone else was speaking. (TV: Deep Breath, Listen, Time Heist)

He seemed to regain a tolerance for alcoholic beverages, (TV: Deep Breath, Time Heist) something his immediate predecessor didn't have. (TV: The Lodger, The Impossible Astronaut, The Time of the Doctor)

Much like his predecessor, the Twelfth Doctor also used hand gestures to extenuate a point, but applied more dedication to his movements, standing firm, while speaking with conviction, though would become more spontaneous when thinking intensely. (TV: Deep Breath, Listen, Time Heist, The Caretaker)

This Doctor made a habit of assigning nicknames to others, giving them names based on their appearance or by an accessory they carried. (TV: Deep Breath, Into the Dalek) This was even when he was wrong, given he kept calling Danny Pink "PE" despite Danny actually being a Maths teacher; the Doctor commented "it just won't stick" in his mind since it's a contridictory job for a former soldier. (TV: The Caretaker)

When not out adventuring, the Doctor could be found jotting down equations and theories on various chalkboards in his TARDIS console room. (TV: Robot of Sherwood, Listen)

Skills
Highly observant, the Doctor was able to point out the Half-Face Man as non-human from his lack of interest in a burnt dinosaur corpse, and later noticed that he and Clara were trapped in a room full of Clockwork Droids because they weren't breathing. (TV: Deep Breath) He was also able to make accurate deductions from observing his surroundings, identifying the Aristotle as a medical ship within seconds of being onboard. (TV: Into the Dalek)

The twelfth incarnation retained his predecessor's ability to converse with other species, such as dinosaurs. (TV: Deep Breath)

Strong and durable, the Doctor was able to support his own weight single-handedly, wrestle the Half-Face Man into a corner, fall out of a high tree branch and shake off the fall quickly, and dive off a bridge into the Thames to swim across the river without being hampered, though the latter two events can be linked to him still being within the early hours of his regeneration, when his physical skills tend to be somewhat exaggerated. (TV: Deep Breath)

Like several of his predecessors, the Twelfth Doctor was both a highly proficient swordsman and skilled in Venusian aikido, using it to defend himself from Abesse and disarming a distracted Robin Hood. (TV: Robot of Sherwood, PROSE: The Blood Cell)

Despite initially forgetting how to pilot his TARDIS due to post-regenerative trauma, (TV: The Time of the Doctor) the Doctor soon mastered his way around the TARDIS console, being able to save Journey Blue by piloting the TARDIS around her, one second before her ship exploded. (TV: Into the Dalek) The Twelfth Doctor also showed a great more skill than most of his previous incarnations at piloting the TARDIS (TV: season 13, Aliens of London, Rise of the Cybermen, The Unicorn and the Wasp, The Hungry Earth, The Lodger, etc) as he managed to always get Clara back in time for her dates with Danny. (TV: Listen, Time Heist, The Caretaker)

Like his second, third, sixth, seventh, tenth and eleventh incarnations, the Twelfth Doctor also displayed telepathic abilities, being able to link his mind with Rusty to try and show the Dalek the beauty of the universe (TV: Into the Dalek) and put Rupert Pink to sleep by placing his index finger on his forehead, editing his memories while he did so. (TV: Listen) The Twelfth described the size of his mind as "a piano dropping on you" if he wasn't careful with telepathic links. (TV: Deep Breath)

Appearance
While a good many of his predecessors, especially the Eleventh, began their lives looking young, (TV: The Parting of the Ways, The End of Time) the Twelfth Doctor started out appearing very much older. He had short grey hair, a hooked nose and sharp silvery blue eyes, with big ears. (TV: The Time of the Doctor) He was of a light build. (COMIC: Chime Time) Clara was confused at the Twelfth's older appearance, saying to Vastra that "he [didn't] look renewed." Even the Doctor was confused about his aged appearance, asking himself, "Who frowned me in this face?" (TV: Deep Breath) Tall and gaunt, he was once described by Clara as looking like a "grey-haired stick insect", (TV: Listen) with Robin Hood describing him as "pale as Milk". (TV: Robot of Sherwood)

Most changed were his eyebrows, which went from "delicate" (TV: The Time of the Doctor) to extremely thick and furrowed. (TV: The Day of the Doctor) Startled by the change, the Doctor described them as "attack eyebrows" which could "take bottle tops off" and were ready to set up their own independent state. (TV: Deep Breath) He later considered his intimidating eyebrows as a major contributor to his gravitas when he assumed the role of leader of the bank heist without any kind of vote. (TV: Time Heist)

Clothing
Immediately following regeneration, he initially wore the Eleventh Doctor's attire, a Victorian nightshirt, and then a coat that he "bought" from a tramp, before stealing a Clockwork Droid's suit in order to masquerade as one.

After having a chance to return to the TARDIS, though, the Doctor chose a new outfit for himself. He donned a navy blue cardigan with a white collared shirt with no tie, matching blue trousers that now covered his ankles instead of being too short, and black brogue boots. Over the top, he sported a thigh-length, dark blue jacket with red lining, often wearing it with the top button done. On his left hand ring finger, he had a pair of gold rings, a normal gold band and a second ring with an amber setting that rested atop the first band. (TV: Deep Breath)

Though his Crombie coat remained a constant staple of his appearance, the Doctor would wear variations of his attire, switching from vested garments with a white collared shirt for simply a dress shirt on its own, such as maroon (TV: Robot of Sherwood), charcoal grey (TV: Time Heist), or black with a white polka dot pattern. (TV: Kill the Moon) Other times, he would dispense with the shirt as well and don a black turtleneck jumper with glittering silver flakes that looked like twinkling stars in a night sky. (TV: Listen, The Caretaker) He also had at least two styles of cardigans- one with shawl lapels and a ribbed waistline (TV: Deep Breath), the other a simpler v-necked waistcoat. (TV: Into the Dalek)

The Doctor picked his look with the intention of "aiming for minimalism", but instead felt like he "ended up with magician" after solidifying his wardrobe. (TV: Time Heist) Additionally, this Doctor was perfectly willing to utilise disguises, namely during his "deep cover" mission to find Skovox Blitzer, although his disguise only went as far as a change of coat. (TV: The Caretaker)

While aboard the Orient Express in space the Doctor wore a very formal attire consisting of a black evening jacket, black trousers, black waistcoat, his black brogue boots, a white dress shirt and a cravat. (TV: Mummy on the Orient Express)

Behind the scenes

 * Like the War and Ninth Doctors, the Twelfth Doctor debuted on television before his regeneration from his predecessor was screened.
 * His first words — "Kidneys! I've got new kidneys!" — keep to the modern tradition of new Doctors commenting on their bodies. Previously, the Ninth Doctor commented on his ears, (TV: Rose) the Tenth Doctor commented on his "new teeth", (TV: The Parting of the Ways) and the Eleventh on his legs. (TV: The End of Time)
 * In DWM 477, showrunner Steven Moffat jokingly answered one fan's question on what colour the Doctor's kidneys now were (he had complained he hated their colour) as "Froon. This is an entirely new colour, which only the Doctor can see."
 * His costume was revealed in DWM 470 and online earlier than planned to spike a tabloid scoop.
 * He starred in The Daft Dimension, a comic strip published in Doctor Who Magazine.
 * Peter Capaldi wanted to wear his wedding ring as part of his Doctor's attire, and requested a prop to disguise it. He was given an amber ring with a gemstone that fits over the top of his original band. The First Doctor also wore a gemstone ring, and as such the Twelfth Doctor is the first incarnation since then seen to sport one. He is also the first incarnation since the Third Doctor to wear an ordinary ring.

Dodicesimo Dottore Zwölfter Doctor Décimo Segundo Doctor Двенадцатый Доктор Douzième Docteur