Good old reverse psychology.

Don't use it against your players, whatever you do. It'll only cause them grief.

Transcript

Yoda: Finally! I thought he'd never go.
Obi-Wan: We were begging him to stay.
Yoda: Exactly! Anyone else would have left days ago. Strong, his mind is.
Obi-Wan: He's too much like his father.
Yoda: Counting on it, I am.
Obi-Wan: You want him to face Vader?
Yoda: If anyone can overcome Vader, it is Vader's son.
Obi-Wan: I still don't understand how Anakin could possibly have survived. He was on fire when I left him on Naboo.
Yoda: Mmm. A mystery... it was.
Obi-Wan: That boy was our last hope. His father will be the end of him.
Yoda: No: there is another.
Obi-Wan: But she's hanging around with complete rogues.
Yoda: Not so different, you were.
Obi-Wan: Yes, but I set him on fire!