The Doctor (Doctor Who)
As a Time Lord, the Doctor has an unnaturally long life expectancy. He can also "regenerate" when near death, a process that heals all his injuries, but also changes his appearance and often causes a period of disorientation. He has already regenerated ten times, however, and Time Lords are typically limited to twelve regenerations.
The Doctor has a genius-level intellect and possesses detailed knowledge of multiple scientific and technological fields. He is also well-traveled and able to fend for himself on nearly any civilized planet.
He is known to have trained in a few obscure alien martial arts, including "Venusian aikido" and "Martian karate". These are primarily associated with the third incarnation of the Doctor; his subsequent regenerations have apparently not kept in practice.
The Doctor possesses a TARDIS that enables him to travel through time and space. Its chameleon circuit is broken, leaving it stuck with the outward appearance of a 20th-century British police call box.
The Doctor sometimes carries a sonic screwdriver, which can emit controlled vibrations. The device has a multitude of uses in addition to tightening and loosening screws.
Recent incarnations of the Doctor have carried a sheet of "psychic paper" that appears to show any document that the bearer deems appropriate at the time, usually some form of identification appropriate for the situation.
The Doctor has occasionally traveled with an armed, canoid robot called K-9.
The Doctor typically has a wide array of seemingly innocuous items in his pockets, as well.