One Hundredth Doctor

The One Hundredth Doctor is an incarnation of the renegade time lord, The Doctor in an alternative future. The One Hundredth Doctor is Nine Thousand Billion years old. In an alternative future the Doctor, in his 24th incarnation (since he had extra incarnations because of River Song) was told a prophecy by three time lords that "Chaos will establish on all worlds!". Eventually the personification of Chaos took over three planets and decided to consume Earth with darkness but The Doctor sacrificed himself to save Earth and died. Since he was given another thirteen incarnations by River this was his last and he was dead, killed before regeneration. But the three time lords resurrected The Doctor giving him unlimited regenerations so he could fight Chaos which would attack the universe forever. After many deaths all because of Chaos, The Doctor had reached his One Hundredth incarnation.

REGENERATION
The Doctor had tried to stop Chaos in many incarnations only to fail and be killed. The Ninety Ninth Doctor was mortally wounded when Chaos attacked his TARDIS damaging the console inside but also hurting the Doctor. The mortally wounded Ninety Ninth Doctor then regenerated into his One Hundredth Incarnation. more to be added