That’s the human race all round… indomitable. The character has determination and an iron will, meaning they are better at resisting mind control and hypnosis. They have something that grounds them, reassures them of who they are and protects their minds against invasion or hypnotic control.

The Indomitable trait gives the character a +4 bonus to any rolls to resist becoming possessed, hypnotised, psychically controlled or similar. In many ways, this trait can also be used to avoid being dissuaded from their course of action – for example, River Song is usually determined to go off by herself despite the Doctor’s warnings. If the Doctor tried to convince her to stay, her Indomitable nature would help her to remain single-minded and determined to do as she wants, even if it isn’t the best idea in the world.