GMPC stands for Game Master Player Character, and most often refers to an NPC that is part of the party, and takes part in all or most adventures with the PCs. The difference being, of course, that this “PC” is played by you, the GM.
There’s a fine line between GMPCs and pet NPCs , but if you steer well clear of that line, GMPCs can be an awesome GMing tool.
The Bad Edge: Pet NPCs
When I first started gaming, I thought GMPCs were all bad — and based on my experiences back then, I wasn’t too far wrong.
In a high school Vampire campaign, for example, our GM had a pet NPC join our party (I’ve forgotten the character’s name, unfortunately — we’ll call him Sven). He was significantly more powerful than our characters, and it didn’t take us long to figure out that we would be going where Sven wanted us to go (and I wish I was exaggerating):
- GM: There tunnel forks up ahead. Do you want to go right or left?
- Players: (After a brief discussion) We want to go left.
- GM: Sven says you should go right.
- Players: We don’t want to go right!
- GM: Sven grabs you, and drags you down the right passage. He’s too strong for you to resist.
Now, there are all sorts of things wrong with that situation (see How to Be a Bad GM: A Primer  for more), but the problems started when our GM decided to cross the GMPC/pet NPC line.
Our PCs were overshadowed by Sven’s abilities, and we were only allowed to make decisions that jibed with the GM’s predtermined story — with Sven as his enforcement mechanism when we started to stray. In this case, Sven added nothing to the party — there was absolutely no reason for him to be there. For me, he’s the classic example of a bad GMPC.
The Good Edge: GMPCs
On the flipside, a more recent example: the GMPCs in my group’s current Stargate campaign. With only three players, we don’t have enough PCs for a standard four-person SG team, so we’ve always been accompanied by a GMPC, either Sarah Gardner (Osiris’s host, for those familiar with Stargate SG-1) or Sheila Stone.
Both Sarah and Sheila bring skills to the table that our PCs don’t have — knowledge of archaeology, first aid abilities and the like. Skills, in other words, that we didn’t take because we weren’t all that interested in them. Both GMPCs are also at roughly the same power level as our characters, and are subordinates in the military command structure.
This makes it very hard for them to outshine us, and they never have. Instead, they’ve helped the party — and best of all, become full-fledged characters in their own right. It’s a very character-driven campaign, and we’ve come to care about the GMPCs, to the point that I can’t imagine the game without them.
Sheila and Sarah are perfect examples of GMPCs done right, and props to our GM, Don , for that — he’s never even come close to the pet NPC line.
Keys to a Good GMPC
A good GMPC should:
- Complement, not overlap, the PCs’ skills and abilities.
- Never overshadow the PCs, especially not in climactic scenes.
- Stay in the background when the players are making key decisions (unless asked for input).
- Provide very occasional clues and hints to help the players.
- Be well-defined characters in their own right, not just collections of abilities.
…and should not:
- Lead the PCs around by the nose.
- Be the center of attention, with the game revolving around him, not the PCs.
- Handle the party’s toughest challenges on her own, because only she has the necessary abilities.
- Be in the foreground when the players are making important decisions.
- Be a proxy PC for a GM who really wishes she was playing instead of GMing.
TT reader and RPG freelancer Walt C. tackled this very topic a few years back, in an installment of his RPGnet column “Keeping Kosher” : When GMs Play . As I read his column, Walt is talking more about what I’ve defined as pet NPCs, rather than GMPCs (who can be good or bad).
He suggests some good ways to keep your GMPCs from becoming pet NPCs, like the Blade Runner Rule: “…create NPCs with a specific life span of sessions or adventures in mind.” If you’re wary of using GMPCs for fear of having them morph into pet NPCs over time, Walt’s article makes a great guide to avoiding exactly that.
What are your personal experiences with GMPCs and pet NPCs, either as a GM or as a player? Do you disagree with the basic division between the two that I’ve outlined here? Are there other characteristics you’d assign to either category, pet NPCs or GMPCs?