26th of March 2025
I feel the need to continue writing in a similar vein to my previous post. In that post I was discussing how rules create a feeling in TTRPG’s, and the difficulty of specific rules niches that create strong elements of genre and feeling vs broader rulesets that can do more things, but not necessarily as well as the more specific rules. I really wanted to expand on this, because I keep coming back to this idea, especially in relation to the VOW. I’ve realised this might take a while, so there will be further posts following on from this, but today I wanted to discuss the idea of light and heavy rulesets.
Rules are useful for a game because they help define what players can and cannot do. You cannot cast spells, because you are playing a barbarian. I can cast spells, because I am a Wizard. In doing so, they also help to define genre. I can create magical spells and weapons because this is a fantasy setting, but I can’t create a laser pistol.
Systems which are much lighter on the rules have less definition on genre and what can and cannot be done. The lightest game system of all, open improv, essentially has no rules about what can and cannot happen – and therefore anything is on the table. This, funnily enough, is some of the hardest improv to perform. Without definition and scope, players can get lost amongst competing ideas, sudden switches in genre, and undefined endings. Similarly, TTRPG’s with lighter rulesets can sometimes go in unexpected directions, especially without a GM of some kind to define the initial scope. My friends and I had some… unexpected discoveries while playing Icarus. This can also be a good thing (and in our case it was) but can also detract from a game, depending on how it manifests.
A heavier system can help define the genre and the scope – the “vibes” as discussed in the previous post. This sets up expectations, players know what they are going into and how they should play within the world. They also know how to behave within that world so that the verisimilitude is retained for all players at the table. However, this comes at a cost. Large rulesets require players to learn a lot of rules, and places extra burden on the GM/facilitator if there is one. I’m going to use an example through Pathfinder 2e (PF2e), which I know isn’t particularly rules heavy compared to some, but it is the crunchiest game that I have played and have experience with, so it is what I’ll talk about here. A light system might simply ask for a dice roll, while a heavy system asks you what kind of dice roll you should be making and what kind of additions/effects can be changing it: An athletics check? What’s your strength score? Are you trained in athletics? How trained are you? Do you have an item and/or circumstance bonus? In some cases, this leads to the feared rules lawyering or GM’s getting stuck in their book searching for the ruling on something. But even more difficult than this, is that it reduces the flexibility of the system.
In a light system, a new or unexpected situation can be handled directly through role play or a single dice roll. In a heavy system, it is sometimes unclear which rule the facilitator should use. In addition, sometimes making a ruling incorrectly can break other parts of the game. There are so many options in PF2e that change the rules or allow for exceptions that if a ruling is poorly made, it can easily invalidate the relevance of other options. For example, a rogue player may argue that their high dexterity score and some custom-tailored clothing allow them to throw alchemical potions from a pouch in a single action (rather than one action to draw and another to throw). You agree with their reasoning and allow it. However, in doing so you’ve completely invalidated the Alchemists “Quick Bomber” feat, which does exactly this. While those familiar with Pathfinder may be aware of how alchemist feats operate, and can decline the player from doing this, new Pathfinder GM’s can very easily run into situations like this and either not realise that an issue has occurred until far later, or spend far too long checking the rules to make sure they are doing the correct thing and completely interrupting the flow of play. In addition, it feels bad to decline a player something like this, especially if they have spent time on their custom-tailored outfit and/or backstory. It goes against the famous “rule of cool” to have to frequently decline players the ability to do things like this.
This, of course, is all a spectrum. I’ve been talking about light and heavy rules, but most TTRPG’s sit somewhere in between. The question is, how many rules are necessary to achieve the “vibe” that you’re searching for? How necessary is the structure to the genre and flow of play? And finally, given how much I’ve talked about light and heavy rules, what the hell could I possibly mean by Soft and Hard rules?
