When The Doctor entered the remnants of his own timeline in order to retrieve Clara Oswald , it is believed the dormant regenerative energies in his body were enough to revitalise the timeline "healing the scar tissue" and causing the collected timeline to congeal into a single being. The two Doctors were pulled into a twisted alternate timeline, but were able to find and defeat the Valeyard, with a little help from an alternate version of The Sixth Doctor. The X Doctor then went into stasis, unsure of weather he would be needed again.