The Thirteenth Doctor (Doctor Who Adventures)

First Time in this form:
Once the Master was defeated by Stormaggedon, he demanded a mirror as a prize.

The Dark Period:
The Doctor's past was revealed by Rassillon, The Doctor's companion left him. This lead to the 13th Doctor's "dark" period, which didn't last too long. He traveled to Gallifrey and purposedly killed someone(Rassillon) for the first time since the Time War.

Once faced with a decision, The Doctor decided to save his companions, but also decided to reform the Trio in exchange of his companion's safety. He was later saved by them.

The Moments of Grief:
Once Alfie's identity was revealed as descendant of The Dagrons, he died, thus leaving The Doctor in a stage of grief where he didn't talk at all for 2 hours and forbidden any kind of reference to Alfie. When Shalek died(but later got revived) because of his selfish reasons of entering the virtual world, he decided to move on.