Shortform article: NPC wants

A referee or Game Master can get an enormous amount of mileage out of working out what their characters want and then setting those goals in conflict.

Let's call received/onerous/reluctant goals 'extrinsic NPC wants' and personal/selfish/ambitious goals 'intrinsic NPC wants'.

Here's a rule of thumb. A sapient character should have a minimum of one intrinsic NPC want and one extrinsic want. These will almost always be in tension or somehow modify each other, because goals are usually unfulfilled due to resource (including time) scarcity. The character's behaviour follows from there.

The sarjent at the head of a pack of tired soldiers?
Intrinsic NPC want: To rest up where it's safe.
Extrinsic NPC want: To double time to report to where the vanguard's meant to have camped before nightfall.
Tension: The sarjent's fear of reprisal may lead her to quick march as directed and be in a foul mood because of it, or set a slower, plausibly deniable pace, camp early, and be consumed with worry.

The wild-looking figure in the woods guiltily holding a fistful of herbs?
Intrinsic NPC want: To not be found out as an illegal warlock.
Extrinsic NPC want: To make a bespoke curse for the man who's blackmailing him.
Tension: The warlock's fear determines the specific ways he will act in creating the curse (disguising his actions and identity, etc).

The old village priest red-faced on the festival day?
Intrinsic NPC want: To drink wine and mutter crude remarks, like on any other day of the year.
Extrinsic NPC want: To present a good image while presiding over the festival.
Tension: The priest's drinking affects his capacity as the master of ceremonies, and his prominence today makes him conceal his drinking.

The tax collector warily riding down the valley road?
Intrinsic NPC want: To amass exorbitant personal wealth.
Extrinsic NPC want: To pay the Duke a plausible amount for the size of the valley.
Tension: Depending on who asks and when, the bulging saddlebag is either personal wealth or for the Duchy. Say, have you paid your passerby fee yet?

The ogre chief presiding over the ogremoot?
Intrinsic NPC want: To get personal revenge on a powerful rival.
Extrinsic NPC want: To make strong, clever, reasonable decisions with the support of the clan.
Tension: If the chief wants to use the role's prestige to enact his revenge, he'll have to disguise it as something for the good of the clan.

This all helps to prevent NPCs seeming flat without taxing the GM's brain or notes. This follows naturally from the outcomes of wants in tension:

• NPCs appear to have their own rich internal lives
• NPCs sometimes do things for unclear reasons, but players can always pull on that thread and discover the reasons, rather than it ever being random
• More ways to negotiate and interact with NPCs
• When PCs change the world, it's easy to quickly tell which NPCs will care about those changes and how they will react

A good deal of this is said to also apply to fiction writing.