I want my NPCs to be simple. They may be similar in mechanics to PCs if PCs are simple. They need to be much simpler, if PCs are complicated and mechanics-heavy.
After all, each player has one PC, while I have 5-10 NPCs in a single adventure, not counting the nameless ones I improvise on the fly.
The degree of NPC complexity should scale with their importance. For a nameless mook, I should be able to improvise the necessary numbers without breaking the flow of narration (see Fate Core: two skills, an aspect, a single stress box). For a secondary NPC, I may spend 3-5 minutes on mechanics. For the main adversary, maybe up to 15 minutes, but I prefer less.
I prefer games without strong correlation between power and complexity. I may need a simple, but powerful creature; less often, but still sometimes, I can use a complex, but only moderately powerful ones.
As for power, I have my NPCs all over the scale, but I like to have a clear indication of how powerful they are.
In perfect situation, I can create an NPC of appropriate power, based on the indicator (level, peak skill etc.) and then play the NPC smart without a risk of steamrolling the PCs or being steamrolled by them.
After all, each player has one PC, while I have 5-10 NPCs in a single adventure, not counting the nameless ones I improvise on the fly.
The degree of NPC complexity should scale with their importance. For a nameless mook, I should be able to improvise the necessary numbers without breaking the flow of narration (see Fate Core: two skills, an aspect, a single stress box). For a secondary NPC, I may spend 3-5 minutes on mechanics. For the main adversary, maybe up to 15 minutes, but I prefer less.
I prefer games without strong correlation between power and complexity. I may need a simple, but powerful creature; less often, but still sometimes, I can use a complex, but only moderately powerful ones.
As for power, I have my NPCs all over the scale, but I like to have a clear indication of how powerful they are.
In perfect situation, I can create an NPC of appropriate power, based on the indicator (level, peak skill etc.) and then play the NPC smart without a risk of steamrolling the PCs or being steamrolled by them.