Your Favorite Core Mechanic sans Setting?

[Khaalis]

Thanks everyone for the comments and suggestions. I am currently first looking at Core Mechanics, but am interested in other system aspects as well; any favorite mechanic really, though Combat systems and Magic systems are pretty high on the priority list. I am doing research because my group is currently messing around with making a system of their own and I'm not real keen on where they are going with the mechanic.

Currently the concept they are going with is the core mechanic will be based on a single roll of XdY, the single highest die result is your result, but if you get more than 1 of the highest die result your result goes up by +1. (ex: if you have 2d6 and roll 2 6's the result is 7)

X and Y are determined by Attribute Rating (1-5: determines number of dice) and Skill Rating (d3 - d12). So if you have say Agility Attribute at 3 and Stealth skill Rating at d6, your roll for Stealth would be 3d6, opposed by say a guard's observation rating.

They are currently looking at using the 9 nWoD Attributes and then each skill being tied to an attribute. They also plan for Most rolls to be opposed rather than static target numbers wherever possible, for instance even a Lock would have an die rating and get to "roll" its resistance to being picked (ex: a simple lock might have a 2d4 rating, so as long as the PC can beat the GM's possible max roll of 4, they'll succeed).

There are also some other rules such as:
* Max of 5 dice regardless of bonus dice.
* Step Up: Step up your die type by 1 at the cost of 2:1 dice ratio (round down). Ex: 3d8 steps up to 1d10
* Step Down: Reverse of step up, but still at 2:1 ration. Ex: 3d8 steps down to 6d6 (technically 5d6) as they keep refusing to look at an overflow mechanic for dice beyond 5.

I've pointed out flaws in the math, but currently falling on deaf ears.
That said...
We've looked at many other games and they are stealing concepts from various systems such as being a lifepath based system similar to Burning Wheel, using concepts like Aspects from Fate or Traits form Numenera, etc. However, for my own sanity, I'm toying with doing my own spin-off with what I consider a more balanced and affective Core Mechanic.


Oh, and as a quick comment to Saelorn...
I'm not sure exactly what you mean by same probability distribution for d20 and 3d6 systems. d20 is Linear and 3d6 a Bell. Very different probability curves. For instance in d20 you have deviation of 5.77 from mean with a flat 5% chance of any number, but in 3d6 you have only a 2.96 deviation. It may not seem much different but it makes quite a bit of difference. For instance you have a 5% chance to roll a 10 in d20 but a 12.5% chance of rolling a ten in 3d6.

 

[The Crimson Binome]

I'm not sure exactly what you mean by same probability distribution for d20 and 3d6 systems. d20 is Linear and 3d6 a Bell. Very different probability curves.

BRP uses percentile. Both d20 and percentile have a flat distribution, where any sort of 3d6 (like GURPS) is going to give you a bell curve.

Or, more generally, increasing the number of dice rolled will increases the chance that their sum is close to the average expected value. Any sort of single-die system (whether that's d2, d20, or d100) is going to have a perfectly flat distribution. A system where you roll 20 twice is going to have a very steep bell curve (as any fan of Disintegrate could tell you).

Using opposed rolls for everything is actually a pretty good way of ensuring that nothing is auto-succeed or auto-fail, though. Opposed percentile rolls are actually my favorite way of guaranteeing that, but it seems like your group is caught up in creating a "fun" dice system, rather than a mathematically regular one.

 

[nomotog]

I really like my core mechanics to be simple because your going to be piling a lot on top of it and a nice simple start gives you a lot of room to grow. The D20 is my choice, but if you don't want that because it's squiggly use a hand full of D6. I forget what system it was, but it was basically you got to roll one dice for each ability point and you wanted to roll above a number to get the right amount of successes. It was maybe a little complex on paper, but it wasn't hard to do in game.

Another idea I kind of like isn't in a table top RPG (far as I know). I really like how in the new fallout games 3NV there just isn't rolling. You find a level 50 lock, then you need level 50 lock picking to pick it. No question. It would run into trouble with DM meta gameing, but if you attached a economic system to it that allowed you to raise or lower your skill and then a consistent world design, it might work?

I really like how the maid RPG handles HP. It's not HP, but a stress and it doesn't count down it counts up. Then when you get too much, you basically stress out and have to act out some kind of funny thing on your character sheet. Making it stress rather then physical trauma is nice because you can use the same failure punishment for any challenge and it also gives you mechanical reasons to RP and engage in different flavor bits.

When it comes to skills, I like how D&D5 edition dose it, or how it works in my head anyway. There is no skill list, you can just be given proficiency in anything or everything so it's a really flexible system. because proficiency don't stack, you don't have to worry about overlapping proficiency you can also cut them as broad or as narrow as you want because you never directly pick on over another. They always come in classes, backgrounds or feats. So what if the sports car skill is kind of narrow, it's never going to have to directly compete with the all cars skill.

 

[Neonchameleon]

Cortex Plus - each factor involved is represented by a dice (d4-d12), you roll your dice pool and take the two highest. Any 1s create complications.

PBTA: 2d6+Stat - 10+: Success, 7-9 Partial Success 6-: Consequences.

 

[Khaalis]

Cortex Plus - each factor involved is represented by a dice (d4-d12), you roll your dice pool and take the two highest. Any 1s create complications.

PBTA: 2d6+Stat - 10+: Success, 7-9 Partial Success 6-: Consequences.

Cortex Plus is only found in Smallville and Leverage correct? What are the "factors" that make up the dice pool? How different is it from Marvel Heroic Roleplaying (MHR)?

OOC - Any experience with Cortex Classic (or Earthdawn since its effectively the same concept but with exploding dice)? Effectively it is (Skill dX) + (Attribute dX) vs. TN.

As for the Apocalypse Enigine (PBTA), how different is it from Dungeon World or is it identical? How much experience do you have with it? Our group wasn't overall thrilled with Dungeon World but that may be because the classes were simply too simple and too D&D...

 

[Neonchameleon]

Cortex Plus is only found in Smallville and Leverage correct? What are the "factors" that make up the dice pool? How different is it from Marvel Heroic Roleplaying (MHR)?

Smallville, Leverage, Marvel Heroic Roleplaying, and Firefly are all Cortex Plus games. What differs between the games are the factors you roll:

Smallville: Relationship, Value, Distinction, Asset, Opposing Stress
Leverage: Stat, Role, Distinction (d4 or d8) Asset(s), Opposing Complication
Marvel heroic: Distinction, Solo/Buddy/Team, Powerset, (Powerset 2...), Specialty/Resource, Asset, Opposing Complication/Stress
Firefly: Stat (Physical/Mental/Social), Skill, Distinction (d4 or d8), Asset, Opposing Complication

I'm simplifying a fair bit there of course. And the most alike games are Leverage and Firefly, with the Leverage protagonists generally being a lot more versatile and competent - and complications in Leverage being something you deal with while in Firefly being things you work through. Also MHRP has a far more detailed injury system than Leverage or Firefly where hurt is just another form of complication.

OOC - Any experience with Cortex Classic (or Earthdawn since its effectively the same concept but with exploding dice)? Effectively it is (Skill dX) + (Attribute dX) vs. TN.

Cortex Classic is very swingy for what it does - and I can not see a skill of d12+d2 as other than an ugly mess I'm afraid.

As for the Apocalypse Enigine (PBTA), how different is it from Dungeon World or is it identical? How much experience do you have with it? Our group wasn't overall thrilled with Dungeon World but that may be because the classes were simply too simple and too D&D...

Dungeon World is a PBTA game - not a very good one in my opinion because it's trying to weld two very different things together. It's like someone took a superb motorbike engine and tried welding it into a pickup truck. Nothing wrong with either approach - but that engine isn't the right tool for the job. If you don't mind profanity give base AW a look - if you want something more sensibly written, try Sagas of the Icelanders. (The best of the family in terms of writing and game is IMO Monsterhearts, but although it's an amazing game playing Monsterhearts with the wrong group would be absollutely dire so I can only give it a cautious recommendation).

 

[GMMichael]

Currently the concept they are going with is the core mechanic will be based on a single roll of XdY, the single highest die result is your result, but if you get more than 1 of the highest die result your result goes up by +1. (ex: if you have 2d6 and roll 2 6's the result is 7)

X and Y are determined by Attribute Rating (1-5: determines number of dice) and Skill Rating (d3 - d12). So if you have say Agility Attribute at 3 and Stealth skill Rating at d6, your roll for Stealth would be 3d6, opposed by say a guard's observation rating.

This sounds viable and fun. Let us know how the playtesting goes, and (sorry if I overlooked it) how increasing challenges goes. E.g. one WoD had opposing dice pools, if I recall...

 

[Celebrim]

BRP has the most elegant character advancement of any game, IMO.

The SAN mechanics for CoC are also amazingly elegant in the context of a game that is not supposed to 'end well'.

Burning Wheel's character burner is one of the most elegant character creation systems ever, if not the most elegant. (I wish I felt the rest of the game was equally elegant.)

Chill 2e also had really elegant character generation.

HERO's speed chart, and similar implementations of time tracking like in Advanced Hackmaster, are really cool in concept albeit on the scale of complexity that I feel they'd be most ideally captured in a video game to handle the overhead. HERO also has really elegant generic mechanics - much better in my opinion than GURPS.

GURPS/GULLIVER had really elegant methods for dealing with differences of scale, by leveraging what was probably GURPS's single best mechanic - the non-linear table for dealing with varying distance. I noticed a similar table showing up in M&M, which was also elegant.

WW's 'Storyteller' system for the original Vampire had a number of really elegant mechanics that were killed by its otherwise poor mechanical implementation. Tracking humanity could have been really cool though, and the never quite realized idea of combining skills and attributes on the fly to deal with propositions could have been cool had the system been crafted better.

WEG's D6 Star Wars was just filled with system elegance, from its 'd6 dice poll vs. difficulty', to it's 'force point = moment of shining awesomeness' to 'alignment tracked concretely through dark side points' to it's use of a 'wound track' to its elegant handling of scale. On the other hand, chargen was uninspired (particularly it's racial mechanics were poorly thought out), and it didn't scale well (among other things, it's jedi problem - however true to the source material - makes D&D's similar wizard problem look tame). Overall though, one of the most elegant systems ever.

I loved the level of refinement you could give magic items in MERPS and Rolemaster. The amount of flavor you could put in it was amazing. Sadly, that degree of versatility was largely tied to the fact that the underlying system was filled with an equivalent amount of complexity. I've tried on several occasions to import that level of mechanics = flavor to magic items, and learned the valuable lesson that large numbers of fiddly modifiers are just too complex to track outside of a computer game (where they are awesome).

The original Fallout video game, with its D&D like level mechanics, concept of 'Feats', and BRP like skill system has to be listed as one of the most elegant RPG systems ever.

My short list of most elegant PnP systems ever would be BRP, D6, and D20.

 

[Jhaelen]

I didn't see any mention of 13th Age's escalation die which I consider a really neat idea.

 

[Khaalis]

I didn't see any mention of 13th Age's escalation die which I consider a really neat idea.

Can you expound? I'm not that familiar with 13th Age.