Let's Talk About Core Game Mechanics

[500 Toads]

BRP-style percentiles are very straightforward and allows degrees of success (e.g. CoC 7E having critical, extreme, hard and regular successes, in addition to regular failures and fumbles). They can be made a bit more complicated (e.g. Runequest in Glorantha's handling of percentiles exceeding 100%), but don't have to be. Odds being straightforward to estimate... is actually a mixed bag, I'd say, because for some groups maybe you want things to be harder to precisely calculate at the table in order to encourage more intuitive play versus calculation.

Having a skill system paired with occupation and personal-interest skills, in addition to progression based both on using skills and on training/practice, also permits many peculiar character concepts.


If you want something a bit wilder and wider-ranging, I do like the die system in Shadowrun Anarchy 2.0 -- a straightforward attribute+skill d6 die pool system with ~fixed target numbers and #success thresholds, but where one can declare dice as 'risk' dice making them more valuable when they roll successes but also enabling glitches (depending on the number of 1s on the risk dice); and where various specialized advantages can provide a limited amount of "risk reduction" to make it safer to declare more risk dice. If you want a style where, say, somebody can declare that he's going to dive while shooting in mid-air from an angle the target wouldn't expect, for a greater chance of success but also a greater chance of catastrophic failure of some sort, that's a pretty neat way to do things.

 

[Thomas Shey]

I kind of lean into dice pool systems because its usually easier to get somewhat consistent results once you know how many dice are going to be involved. I'm not a fanatic about it (I'm almost done running a d20 based game and am about to do a D100 based one). Second is probably D100-roll-low systems because I think it becomes intuitive pretty quickly (basically as soon as people can get over high-is-good) and you can bake a lot of results into one roll fairly easily.

 

[Bill Zebub]

My favorite core dice mechanic, even thought I've tired of almost everything else in the system, is from The One Ring. d12 + Nd6, where N is mostly skill with a few possible modifiers. A 12 on the d12 is automatic success and 1 is bad, and each 6 on the d6's is a bonus success, which can be used for extra damage if a weapon, or helping friends who failed their tests if a skill, and some other things.

 

[definiteFreakyFishGuy]

As an example of my own, I really like the core mechanic from the Ironsworn games: roll a d6+mods, then compare to 2 separate d10s as target numbers. You can get no success, partial success (beat one of the d10s) or a full success (beat both of the d10s). I do not really if there is a critical system, but I don't think so, nor do I think it needs one. I like that the systems is a little chaotic and unpredictable, as well as the built in multiple degrees of success. One think that could be interesting is to add a Daggerheart "Hope and Fear" style "tenor" element. You could designate the d10s as a Complication die and a Opportunity die. Any time you get a partial success, you further interpret and impact the result based on whether you bet the Complication die or the Opportunity die.

In Sundered Isles (Ironsworn: Starforged expansion), there is an optional rule that (I think) does exactly what you are talking about. The optional rule assigns to the d10stwo moons of the world, Cinder and Wrath.

From the free sampler pdf (pg 7):

Cinder is hot: aggressive, passionate, resolute, physical. Wraith is cool: careful, mysterious, cunning, unearthly. On a match, choose which has the most influence.

 

[Errant Thinking]

I am also making my own system right now and I am striving for

• minimal computation during play, fast play with good flow
• intuitive and simple character sheet that informs you what you can do and directs roleplaying
• resolution mechanics that enable player choice, has consequences & moves the narrative forward,
• every game action aligns with narrative reasoning

A good core mechanic is one that supports the intended design of the game, and for my intended design, I'm currently looking at a counted dice pool.

You start with two dice for every save. The narrative situation sets the difficulty, which is how many successful dice you need to roll to save. Default to needing one of those dice in the pool to roll under a threshold set by the character's relevant attribute. Decrease the difficulty or increase dice by improving your narrative positioning, or increase the dice you roll by spending resources, either a HP/stress or some of your relevant attribute that decreases after the save, thus decreasing odds of success in the future.

This has mixed outcomes from the dice pool where you count successes and failures and each state moves the narrative forward. So you can push yourself to try to succeed but in doing so risk some chance of that backfiring worse by straining yourself (there is a bad outcome threshold higher up on the die with less probability, also on your character sheet. Any bad roll means something bad happened, even if you succeeded).

Besides the resolution mechanic and the tie to attributes as health and a resource, there is also a slot inventory system like Mausritter that negative conditions can take up slots of your inventory, as narratively makes sense. And there is on character sheet tracking of wounds and their types, ideally as tokens or clear icons so at a glance you know you got cuts, scratches, etc.

My focus atm is on the generic character parts for a strong foundation so I can build more specialized things for a game or setting on top of it.

 

[PoketheBear]

I like roll under systems - Dragonbane to be specific. But currently playing Household which uses d6's and has a push-your-luck mechanic. I don't know if I'd want that all the time, but it is fun.