One of the most controversial questions in the tabletop RPG hobby is ‘What makes a good game’. Entire philosophies of play are built around the idea that you don’t need much in the way of mechanics, and entire other philosophies of play are built around the idea that those mechanics are essential to creating the desired experience in a session. The reality, of course, is messier than either of these. We’ve all heard that “Every game is good with a good GM”, but that doesn’t actually mean that every game system that makes its way to a group’s table is, well, good.

In order to fairly review a game you need to understand what the game brings to the table, yes, but you need to understand the same for your GM. Good GMs can run good games with bad systems by working around or even ignoring aspects of a game system, as well as supplementing the system with experience or house rules from other systems and campaigns. Similarly, bad GMs can create bad experiences with good games by interpreting rules too rigidly or loosely, failing to do the right amount of prep for the system, or using the mechanics for situations in which they weren’t intended to apply. While no game can fix a bad GM who is truly set in their ways, good games can, though good writing, help inexperienced GMs avoid the pitfalls I’ve mentioned.

If the GM matters as much as the game, it’s important to figure out what successes and what shortcomings are coming from where. This helps you fairly judge the game, give feedback to your GM, and also determine what sorts of games match up with your GM’s style. This all comes down to three broad processes. Fiction is taking setting elements and translating them into game terms, providing the framework to prep sessions and campaigns. Information is the presentation of those setting and character elements to players in-game in a way that informs what in-game actions can be taken. Adjudication is the interpretation of game mechanics, of knowing what it means when dice hit the table and what happens next. While games range in quality in all of these aspects, they also range in approach, meaning that the game-GM split is bound to be a bit different for every system.

Fiction

All GMs know how to prep, but creating game fiction is knowing what to prep and what that prep actually means for the upcoming game. Imagine for a second that you want to run a game set in the universe of Star Wars; you may be using one of the licensed systems for Star Wars, or you may not. Either way, you’re imagining an opening scene where the characters flee from a crashed starship under fire from stormtroopers. It’s a cool and dramatic opening, it’s going to be great. There’s just one problem. The classic Star Wars trope for stormtroopers is that they’re terrible marksmen; blaster bolts are flying everywhere but no character actually gets hit. In the world of Star Wars, your characters should be able to run away without trouble. In a game of Star Wars, that highly depends. If you were to roll all those shots in many systems, you’d perforate the characters and the campaign would be dead before it began. Even if the characters and your story survived, immediately tending to the wounded after being attacked by bog-standard stormtroopers may not conform to the feel you’re going for.

The key here is that across several possible systems, the GM can always get the intended effect for the scene if they know the Star Wars tropes. But, if one of those systems treats stormtroopers correctly, it’s better aligned to the game fiction.

Another consideration is simply how a system models the game’s fiction, and at what level of detail. For the purposes of the story and the setting, how much do you need to know? The more rules a game has, the more those rules are going to impact the fiction, so it becomes important that they’re impacting the fiction in the way you want. This is not quite the same as detail for the game’s sake. More rules impact the fiction more, of course, but they’re usually designed the way they are to make the gameplay more detailed and interesting. When the GM is managing information that’s relevant to gameplay, they’re interacting with the rules in a different way than when they’re managing how the rules affect the fiction of the setting.

Information

How do you describe a room in a dungeon? How do you let players know that their spell had the intended effect? Are you going to tell players they’re 30 feet off the ground, or say ‘it’s a long way down’? These are examples of game information. The management of game information varies wildly; many games in the OSR tradition prefer that all information presented by the GM is gameable, and therefore that almost nothing is abstracted. If the secret key is hidden in an indentation in the bottom of the jewelry box it doesn’t require a ‘search check’, it requires a player to declare that they’re going to pick up the jewelry box and look. In a game like Fate, though, the rules interact more directly with what’s in the room, and it becomes important for the players to understand what would allow them to Create an Advantage for an upcoming encounter, or what they need to Overcome to get closer to their goal. There’s no wrong way to use rules in presenting information; the Fate method is more prescriptive, but the OSR method requires more creativity and work.

One common liability of many game systems is to be fairly sparse with actionable information outside of combat. This is getting better, but it’s an important question if you want mechanical support for things like social interaction or exploration, or if you just want to make it up on the fly. My experience tends to be that good mechanics that present you with information and procedures for the activities you’re interested in using for your game almost always work better than trying to wing it; either the mechanics help lighten the load or they inject new ideas and randomness into the game that makes it more fun. Either way, while mechanics create more game-relevant information, they also make for additional rolls and tests that the GM must adjudicate.

Adjudication

You rolled a 6. What does that mean? Telling you nothing else you don’t rightly know, but depending on the system that could be an outright failure, a massive success, or a chance to roll again. Those nuances tell us exactly why game adjudication is so important. To adjudicate a roll, a GM needs to set a target and then explain what happens when the die lands. That target number part is often poorly explained, which is why there are many games which take it out of the hands of the GM. The best example of this is PbtA, which in its traditional examples has set thresholds for its three dice outcomes, and precious few modifiers (usually a character’s stat and maybe a +1 from another character helping or the outcome of a previous action). This relative ease of roll math is offset by the fact that the probabilities don’t change, making PbtA only really work for games that roll dice only when there are significant stakes. A very different (but still well-designed) roll approach comes from percentile systems like BRP, where the character’s rating in a skill is equivalent to the probability of that character succeeding on the roll. In that case, the GM can usually do some quick mental math and figure out if the difficulty needs to be adjusted, though like any game it’s easier with good skill descriptions with numerical examples.

So the target number is decided, and the die is rolled. Assuming it’s not in combat (where everything should be obvious), the GM has to decide what happens next. Sometimes, the game just gives you ‘yes’ and ‘no’, and it’s up to the GM to contribute nuance if that doesn’t quite fit. Other times there are procedures. PbtA (an example of good adjudication rules in multiple ways) has its three outcome die roll, and all three outcomes have clear mechanics. If the roll is a success, the character gets what they want. If the roll is a middle result, the character still gets what they want, but there is a complication or mitigation. This works best when those complications and mitigations are described specifically in the given move being used. If the roll is a miss, the GM gets to make a move (and those moves are laid out in every game). The character usually doesn’t get what they want as well, but that’s not actually what the rule is…the rule is that the GM gets to do something, taking narrative control.

Just as with everything else, some people like loose adjudication, while others like it more defined. With Electric Bastionland’s roll-under mechanics, you need not define much of anything in the context of rules. On the other hand Torchbearer has specific lists of difficulty modifiers (factors) for every skill check in the game, as well as a specific, binary choice for the GM to make should the player fail a roll (twist or consequence). Some people find Electric Bastionland easier to run, some people find Torchbearer easier to run. Neither is wrong.

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Matching GM to system to group is an important prerequisite for a good game and a good time, but most of us aren’t so precious as to only be able to have fun with one game. Similarly, the GM is the one who takes up the slack if the game system fails at one of the elements above. A game could fail at fiction by advertising itself as a breezy pirate game and then requiring algebra for every cannon shot. Information can be let down by something as simple as a difficulty table mismatch, where the ‘average’ task is only successful by a typical character 20% of the time. And although it sounds difficult to fail at adjudication, if your task resolution process gets complicated enough, then it’s altogether possible that a player won’t actually know what they rolled and if they succeeded.

In the end, a GM may compensate for a light set of mechanics as much as they do for an outright bad one, or pare back from good mechanics if it’s not their style. When considering if the system is a match, you must ask yourself what the system is adding to your game. You may find the fiction of Exalted is intriguing while the adjudication is a raging garbage fire (that is, in fact, my opinion). You may find you really appreciate how much information GURPS gives you but thanks to its granularity the fiction just doesn’t work for what you want to run.

As we all likely know, a good GM can hide a lot of faults in a game system, simply by knowing when to use their judgment and when to can bad rules. But no matter how good the GM made the game, the system still didn’t meet their needs. When you’re considering if a system is working for you, consider what it’s giving you for your game’s fiction, your in-game information, and your mechanical adjudication.

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