This is the first time I've asked a question here, so I'm going to be extra cautious to avoid spoilers.
In the final episode of Series 10, the Doctor begins the episode with
a head wound inflicted by the Master and Missy. Then he is knocked unconscious by an electrical shock when a Cyberman grabs him. Later on, his hand begins to glow with regeneration energy, but he forces the regeneration to stop.
Then, at the end, The Doctor is
blasted repeatedly by Cybermen and again starts to regenerate, but he refuses to allow it to happen and instead blows up the entire level, destroying the Cybermen. He delivers his "I hoped there'd be stars" line and closes his eyes.
My question is, at this point, did the Doctor
die? It is clearly possible for a Time Lord to die before he is able to regenerate, and it can even happen because the Time Lord refuses to allow the process to happen, as in "Last of the Time Lords," the Master (appeared to) die rather than regenerate just to spite the Doctor.
I'm not sure which is the case. It seems possible that the Doctor did
die but was restored to life by Bill's tear, the same way that she was restored by Heather's tear. (Bill says that she returned him to the Tardis so that he could "rest in peace," so she seems to think he is dead.) But wouldn't that mean that the Doctor is now a water creature rather than a Time Lord? Or, was he just unconscious, but the regeneration process was still underway?