Load Bearing Rules in TTRPG

Professor Murder · 2026-04-24T15:45:07+0100

So I was inspired by a comment I made on another thread which has me curious.

Very broadly, any given rule in an RPG is either essential or optional. By essential, I mean load bearing rules that if you change them, it has knock on effects. Often times, these are base systems that make up the rules framework of the game in question.

Examples from DnD:
Encumbrance is an optional rule. Removing it does little. It only interacts directly with systems like movement or exhaustion.

Rolling d20 and adding modifiers to overcome a DC for a task is a load bearing rule. If you decided to change it to rolling 2d12 for example to change up the curve, you are effecting fundamental systems in the game. Existing bonuses, penalties, and DCs are all calculated based on using a d20 for RNG.

So my question is: Do you ever change load bearing rules?

GMMichael · 2026-04-24T16:02:50+0100

(Encumbrance as an example reinforces my mistake that this thread is about load-bearing characters.)

My game of choice, Modos 2, provides rules in tiered modules. The lower the tier, the more load it bears. Also, many rules include a dependency reference that shows on what rules they depend.

I haven't had a need to change the load-bearing rules yet, but if I did, I'd have a bit of help determining what the consequences would be.

Professor Murder · 2026-04-24T16:06:38+0100

More modular game design I would expect is more flexible and as a result may not even have any real load bearing rules.

Umbran · 2026-04-24T16:28:47+0100

Professor Murder said:
More modular game design I would expect is more flexible and as a result may not even have any real load bearing rules.

Quite the opposite - in a modular system, the "load bearing" bits are the framework and interfaces that allow the modules to interact smoothly. If you take them out, you have two modules, and no clear idea of how they'd work together in play.

RenleyRenfield · 2026-04-24T22:21:37+0100

I did this for WoD d10 pool system, specifically for Vampire the Requiem hack i have (link)

The idea was that outside of combat, successes were often just 1 or 5 and kinda felt unused with 2, 4, or 7 were rolled. So I changed the core rule to 'spend' successes instead of a threshold of 1 or 5+. This is a fundamental change to the game as in various areas you can now spend to search, influence, and many other things.

mearls · 2026-04-24T22:31:20+0100

If the game has any sort of action economy, your resource cost (how much it costs to create effect X) and resource throughput (how may resources you can spend per turn/round/whatever) are things you can't mess with. That's why concentration in 5e is a rigid rule. It ensures you can't stack the bonuses (or debuffs) from too many spells at one time.

It's actually a source of deep imbalance in 5e. Reactions were never supposed to carry more weight than an opportunity attack. Any spell or feature that allows you to deliver damage via reaction on the regular is adding damage on top of a character's full output.

Professor Murder · 2026-04-24T22:38:46+0100

mearls said:
If the game has any sort of action economy, your resource cost (how much it costs to create effect X) and resource throughput (how may resources you can spend per turn/round/whatever) are things you can't mess with. That's why concentration in 5e is a rigid rule. It ensures you can't stack the bonuses (or debuffs) from too many spells at one time.

It's actually a source of deep imbalance in 5e. Reactions were never supposed to carry more weight than an opportunity attack. Any spell or feature that allows you to deliver damage via reaction on the regular is adding damage on top of a character's full output.

A rules change you could make to address this would be to combine the bonus and reaction actions. Give the PC only one per round, forcing them to make choices.

mearls · 2026-04-24T22:57:11+0100

Professor Murder said:
A rules change you could make to address this would be to combine the bonus and reaction actions. Give the PC only one per round, forcing them to make choices.

That would be a very nifty way to gate reactions!

Morrus · 2026-04-25T00:15:39+0100

Man, using the terms 'load bearing' and 'encumbrance' in your post are going to cause a lot of confusion. Good luck!

Thomas Shey · 2026-04-25T00:41:13+0100

Professor Murder said:
So I was inspired by a comment I made on another thread which has me curious.

Very broadly, any given rule in an RPG is either essential or optional. By essential, I mean load bearing rules that if you change them, it has knock on effects. Often times, these are base systems that make up the rules framework of the game in question.

Examples from DnD:
Encumbrance is an optional rule. Removing it does little. It only interacts directly with systems like movement or exhaustion.

Rolling d20 and adding modifiers to overcome a DC for a task is a load bearing rule. If you decided to change it to rolling 2d12 for example to change up the curve, you are effecting fundamental systems in the game. Existing bonuses, penalties, and DCs are all calculated based on using a d20 for RNG.

So my question is: Do you ever change load bearing rules?

With great, great care. And understanding that I'm probably reworking a game system in very fundamental way and potentially unpredictable consequences. And at that, very rarely.

Because I've been casual about it a couple times in my younger days, and found out the problem of doing so the hard way.