Initially stern and ruthless, but in reality kind and forgiving, the Twelfth Doctor was the first incarnation of the Doctor’s second regeneration cycle, bestowed upon him by the Time Lords at Clara Oswald’s urging at the end of the Siege of Trenzalore.
Assured of the survival of Gallifrey, the Doctor was no longer chained down by guilt, becoming a less amiable character, as he no longer needed to cover the pain of what he thought was the extinction of the Time Lords, with a withdrawn attitude who habitually questioned his own goodness.
He often dispensed with niceties in a tense situation, becoming cold and calculative when needed. However, despite his ruthless exterior, the Doctor was actually deeply caring and empathetic, always striving to help others for the sake of being kind.
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