There are many reasons for adventurers to adopt aliases. And all of them make good adventure material. Because if they're concealing their identity, you just have to ask the simple question: What if they get found out?

You don't necessarily have to have anyone find out who they really are, but this question should always be uppermost in their minds. Any slip or clue at all dropped by the heroes can lead to panic, or desperate measures. And fun for all!

Transcript

Leia: Why did this Lando want to shoot you, Han? Or should I say, "Freddo"?
Han: Ifa you calla me Freddo, I gotta speaka like-a dis.
Leia: Okay, Han. Is this a safe place? Are they sympathetic to the Rebellion?
Han: Right. We better use aliases.
Leia: Good thinking.
Han: Oooh, I've been thinking about this. I'll be Iago.
{beat, Leia stares}
Han: And Chewie, you can be Jafar.
Chewbacca: Perhaps names not generally associated with utter villainy?
Han: What better cover for such upstanding citizens as ourselves?
Chewbacca: Laurel. And Hardy.