The Sixth Doctor
Story: Time and the Rani (1987)
Cause of Regeneration: Unknown. The TARDIS was hijacked by the Doctor’s old enemy the Rani. When she entered, he was already regenerating. Note: Colin Baker had been fired prior to shooting. Sylvester McCoy wore a wig for the scene.
Last Words: N/A
The Seventh Doctor
Story: Doctor Who: The Movie (1996)
Cause of Regeneration: Shot/Botched operation. The Doctor was caught in the middle of gang warfare and was shot. Taken to hospital, the usually routine operation was not suited to his alien biology and killed him.
Last Words: “The Master! He’s out there…”
The Eighth Doctor
Story: The Night of the Doctor (2013)
Cause of Regeneration: Spaceship crash/potion. On Karn, the Eighth Doctor was given a special potion that allowed him to chose his next incarnation. Due to the ongoing Time War, he chose to become a warrior.
Last Words. “Physician, heal thyself.”
The War Doctor
Story: The Day of the Doctor (2013)
Cause of Regeneration: Old age. After saving Gallifrey with his future selves, the War Doctor returned to his TARDIS and began to regenerate. We don’t see the complete change, but his final words heavily suggest he became the Ninth Doctor.
Last Words: “I do hope the ears are a it less conspicuous this time.”
The Ninth Doctor
Story: The Parting of the Ways (2005)
Cause of Regeneration: Vortex exposure. Rose Tyler was burning up after soaking up the power of the Time Vortex. To save her, the Doctor took the energy from her, even though he knew it spelled his doom.
Last Words: “Before I go, I just want you to know, you were fantastic. And you know what? So was I.”