NPCs are *important. Great stories have great characters. Their actions bind the scenes and locations to the adventure. They move the story forward.
NPCs are dynamic, much more so than the campaign's history or landmarks. NPCs have their own paths and reactions. Interaction between players and NPCs might create even more paths and reactions. Some of which continue out of sight of the players. When such a path comes back to the players they might trace it back to their interaction with the NPC. Making your world feel alive and allowing the players agency within it.
A short background and motivation on the NPCs allows you to see through the NPC’s eyes. To see what they might do out of sight of the players.
Major vs minor NPCs
- Major: Limit yourself to 3 major ally NPCs and 1 to 3 enemy NPCs. In this way, players can keep track and remember them.
- Minor: or secondary NPCs breathe life into your world and serve as a pool for primary NPCs. Keep very minor notes on them.
- Importance. How important NPCs are to your world is both stressed by Mike Shea and Brandon Mull.
- New paths and reactions that occur out of sight of the players are what make your world feel alive. Brandon Sanderson described this as the part of the iceberg that is below the water.
- Use the NPC’s motivation to see what his/her reactions and "new paths traveled" are is a point all masters agree on.
- Distinguishing between major and minor NPCs was also proposed by Matthew Mercer.
- Limit yourself to 3 allies and 1 to 3 enemy NPCs. This is consistent with the warning not to introduce too many characters and players at once. See Brandon Sandersonwhen he described the learning curve of your world.