Is there a framework for pnp RPGs that allows you to compare the game mechanics between different editions of a game?

[GuardianLurker]

Now those could be meaningful for multiple game systems.

That would add:
Turn Order/Initiative: Individual/Group/Hybrid; Randomized/Adjusted Order/Fixed Order; Periodic Resets/Purely Cyclical

• 1e and 2e have initiative that is Individual, randomized, with frequent (every turn) resets.
• 3e and later have initiative that is Individual, Randomized, and Cyclical. Though the GMs in all editions tend to change the Individual to Group, purely for practical reasons.
• FFGs Genesys games have a Hybrid/Randomized/Reset initiative. The character roll initiative every turn for party use, and any character can use any roll (once).

Skill "Scale"/"Use"/"Granularity" (no good term comes to mind): Character-based (e.g. Backgrounds as Skills); Broad/Generalized Skills (e.g. D&D 3e, many others); Narrow/Specific
Skills (e.g. GURPS); Skill Trees (broad-to-narrow-to-specialized). Additional variant: Weighted cost by player/system/unweighted.

• 1e and 5e both have Backgrounds-as-Skills, with no weight attached.
• 3e and 4e are both broad skills, with a system specified (and limited) weight attached.
• 2e is a broad skill, with no weight attached. (Ditto for late 1e with the Survival Guides.)
• As a further example, Rolemaster has skills that are specific, arranged in a limited skill tree, with a system-specified weight.

The AC changes are already covered as "roll vs Target" and "increased consistency across the editions", in my opinion.

There might also be a reasonable cross-system "Combat Lethality" term. Super-heroic/Heroic/Death Spiral/Lethal. I'm less sure about the gradations on this, or even if this makes a meanigful difference.

Spoiler: A side discussion

And not to denigrate Deset Gled and GMMichael's points, but categorizing game MECHANICS is a very different thing from categorizing Game Design or Game (Design) Theory. Those are both much more nebulous concepts. Even just the "Rules-Light" vs. "Rules-heavy" debate is evidence of that.

Strangely enough, if you avoid trying to define the terms explicitly, or nail down commonalities in design and philosophy, I think you'd find that most people could sort game systems by "rules-weight". At least, each game relative to each other game. I'll also admit that even that situation would be more inexact than my rough statement implies. There's a lot of "I can't define it, but I know it when I see it" going on here.

 

[aramis erak]

some elements to add to Guardian Lurker's list of things to ID:

Rules approach:

• One single mechanic used for all mechanical occasions. (Includes most PBTA and MegaTraveller)
• Two closely related mechanics (Houses of the Blooded: combat is a variation of the normal resolution, but adds an extrapolation for initiative and actions - the "initiative Risk" is a relatively normal risk roll, but your wagers are how many turns you get in the round, and your initiative is how you rolled on the dice.)
• Two different mechanics to cover all mechanical occasions (Starships and Spacemen {anything but melee, melee},
• Three different mechanics (Palladium Robotech {combat rolls, Saves, skills}, Tunnels and Trolls {combat, saving rolls for non-combat or resistance, casting rules for magic})
• Multiple different mechanics: AD&D (combat, saves, racial abilities, thief skills, Psionics), Classic Traveller (unified combat, but most skills include a unique subsystems; many ignore the special cases and just use the combat roll for non-combat skills.) Palladium Fantasy (Combat Rolls, skill rolls, saves, casting)

Rules Consistency

• No changes from main mechanic(s)
• main mechanics include several exceptions, but all the various special abilities are just applying that handful or two. (2d20 Star Trek Adventures, 2d20 Dune)
• Some abilities are exceptions to main mechanics, but remain close
• Many abilities are exceptions/additions to main mechanics, also calls "rules-by-exception" - D&D 5 goes there with Feats and Class Abilities - both of which are exceptions to the unified resolution mechanic.

 

[GuardianLurker]

That's probably the best (only?) mechanics-based codification I've seen for rules-weight in TTRPGs. (Congratulations!) I've always thought that rules-weight was ultimately about "how hard is this system to learn and master?"

I'd probably combine your "Approach" levels into three: Unified (your first two points), Varied (your next two), and Complex (your last). I've run into game systems that have multiple independent and differing subsystems (I'm looking at YOU, Anima), which I'd regard as "lighter" than differing subsystems that aren't independent, as you could easily play the game without the subsystem and not need any "patching".

On your "Consistency" scale, I'd also distinguish a difference between "removal of limits" exceptions (like DnD 3+ Feats) and "new subsystem" exceptions (like your Classic Traveller skills). Admittedly the last might verge into the "Multiple Subsystems" point of the "Approach" scale. Here I would distinguish based on the scope of the subsystem, with the smaller falling into the "Consistency" category.

And that leads to what I feel most people also lump into the rules-weight category, though I'm not sure it is really part of it. And that's {wiggly hand-wave}Centralization of Authority, or GM-Trust, or System Completeness, or...{/wiggly hand-wave}. I will concede however, that there's an apparent correlation between these stances and the mechanics-based weights you suggest. This area is more properly covered by the discussions that Deset Geld and GMMichael mentioned.

I don't believe the correlation is causal, however. Nor do I think it's a very strong one. But it is there. And trying to define what and how things correlate is not easy (as alluded to). Which is why I prefer focusing purely on the mechanics.

 

[aramis erak]

@GuardianLurker
I've seen some fairly light but multiple subsystem games. A light skill or attribute system for non-combat, a light combat model, and a magic system separate from either.

Rolemaster is a case where it's "heaviness" is only in character gen and advancement; actual play is 3 subsystems: the skill system, the combat system (which uses the skill system, but has different end result methodology), and the pay-the-points to cast magic system. It plays like a medium-light (say 2 of a 0-5), but advancement and character generation look like medium heavy (4/5) to heavy (5/5)

Which reminds me:

Character gen:

• fully random
• roll-place - repeat until filled
• roll all then place (CP2013, CP2020, Mekton)
• Array of values (D&D 4e, 5e)
• spend points in single pool (GURPS, Hero, Mechwarrior 1e)
• Priority then points within the categories (Mechwarrior 2e, Shadowrun 1e-3e, oWoD Atts and Skills)
• Spend from multiple pools (Jackals, CORPS, Savage Worlds, rest of oWoD character values)
• Draw cards and place (DL5a, MSHAG)
• Rate Yourself (Trauma, V&V, EotW)
• Rate the Character by comparison to Pregens (MHRP)
• Auctions (Amber)

Character Advancement:

• Experience points towards level-up (D&D,
• GM Fiat to level up (Daggerheart, D&D 5 {optional}, Pugmire)
• Experience points on separate scale from character gen (Shadowrun 1e-3e)
• Experience points on same scale as character gen (GURPS, Hero)
• Check-rolls Use to Raise (BRP, MegaTraveller)
• Check-rolls, spend to raise checked (Traveller T4)
• Count difficulties used in order to raise (Burning Wheel)
• Count successes and failures in use to raise (Mouse Guard)
• Raise x skills per session by y. (FASA Trek 1-2 skills by 1d10 each)
• None
• Slow in-character action (Classic Traveller)

 

[GuardianLurker]

I think your character generation and advancement categories are a little too fine grained for useful comparisons across the wide variety of TTRPGs.

If I understood Cergorach's first post correctly he is looking for broader "feels like" comparisons. And while you certainly caught some I missed (I had forgotten Amber's Auctions), most of those splits feel like they are internal to a "rating", rather than a rating themselves. For instance, while HOW you roll/spend the dice during char gen matters a lot less than the mere fact that you ARE rolling, especially if you're trying to compare it against some form of point buy.

It does suggest that it might be more useful to think of this as less of a "One Comparison Tells You Everything" and more of a sieve or filter, with "Functional Areas" breaking down into "Categories", and the larger "Categories" having "Subcategories" of their own, before finally reaching the actual concrete description.

Regardless, we're never going to get rid of "Miscellaneous" at any of these levels. There's too much innovation/weird stuff for any descriptive categorization to ever be complete.