Ask questions

Many NPCs will be people who the PCs would know, or least know of, so ask your players about them. They'll care more about NPCs that they help create! Keep the Line in mind. Ask the characters questions that they'd be able to answer. The closer the PCs are to an NPC, the more questions you should ask.

For locals or people PCs know well:

• Are you related to them? How?
• What's their family situation? (Married? Kids? Parents? Siblings?)
• Who else are they close to? Who cares about them?
• What do you like/dislike about them?
• What are they respected for?
• What do others say behind their back?
• What's their most notable feature?
• How have they always treated you?
• What do they seem to like/dislike?

For outsiders, but ones the PCs know:

• When/how did you first meet them?
• When did you last see them?
• What do you know of their family?
• How would you describe them?
• Why do you (not) look forward to seeing them again?
• How have they changed since last you met?

For folks the PCs have heard of but don't actually know:

• What are they known for?
• What is said to be their most notable trait?
• Who do you know who's met them?
• How are they different than what you expected?

For specific NPCs, you can be much more provocative. Frame your questions so that they assert things that you want to be true, while still asking the player something meaningful. When you introduce a mercenary from the Heavy's blood-soaked past, maybe ask, "Why would you never want to cross swords with them?" or "What dastardly deed did you once see them do?"

If multiple PCs know the NPC, spread your questions around. Even better, ask questions that push the PCs towards conflicting opinions of the NPC. If you asked the Heavy what dastardly deed they saw this mercenary do, then maybe ask the Seeker how that same mercenary once saved their life.

Build on the answers your players give you. Clarify and ask follow-up questions, but otherwise treat their answers as if they've been true all along.

I ask Rhianna, "So what makes Elios a good choice to leave in charge?" She says that he helps her drill the militia. Folks have always looked to him when she's out in the Wood. "Why is that?" She says he spent time as a mercenary when he was younger, and has actual experience with this stuff. Interesting!

"Cool!" I say, then turn to Blodwen. "How are you related to him? And what's he like?" She says that he's her uncle (her mother's brother), a hard worker, gruff but always kind to her.

I then ask Vahid what he dislikes about Elios. And he's like "Ugh. He's the worst. Can't take a joke. No sense of humor at all."