So way, wayyy back in April I posted Part 1 of the Design Journal, where I "set the stage" for my vague thoughts on RPG system development. A lot of time and thought has passed regarding this idea of mine, and I've chipped away a little at what I call, for better or for worse, the Tankards & Broadswords RPG. Not especially original, I know, but whatcha gonna do, right?
Anyhow, one thing that I want to hammer down before anything else is the Core Mechanic. I must admit that I am a fan of having One Core Mechanic in a system. That doesn't mean that there won't be the occasional odd roll here or there, so I guess I'm not a Core Mechanic purist, but I like having a system where, when explaining it to a new player for the first time, there's really just one core system idea you need to nail down, like "roll this d20 and get a high number" or "roll these percentile dice and hope you roll low". Basic Roleplaying does a good job of this. They have one standard percentile mechanic, but the rules aren't above asking for a random 1-10 roll or 1-6 roll now and then to determine something that doesn't need the granularity of a percentile roll.
So with that in mind, here's my Core Mechanic. I think it's relatively easy to pick up, quick, requires essentially no math, and is more or less generic enough to be used as a "Core" determination mechanic. To quote my current rules draft:
The High Roll Mechanic
The T&B RPG uses one standard mechanic for determining the outcome of most gameplay decisions - the High Roll. Whenever a character has to make a skill roll, the Player rolls a number of six-sided dice equal to the character's skill rating. The result of the throw, from highest number to lowest, is then compared to an opposing die roll - representing either an attempt by another character to prevent the action, or simply the vagaries of chance and circumstance getting in the way. Whichever throw has the "High Roll" - the highest die unmatched by a die on the opposing side - is the winner.
For example. Two characters are battling each other. The attacker makes a roll with his Melee skill of 4, rolling four dice - 5, 4, 2, 1. The defender makes a roll with his Defense skill of 3, rolling three dice - 5, 4, and 4. The first two dice match up and cancel each other out, but the first unmatched pair of dice - the attacker's 2 and the defender's 4 - determine the result. In this case, the defender wins with a Balance (remainder) of 2. The attacker's 1 is immaterial and isn't considered in the results.
Keep in mind that the number of dice rolled and the overall result has no bearing on how well an action was performed - all that matters is the result of the highest unmatched die - the High Roll. If one character rolls six dice and gets 4, 4, 3, 3, 3, and 2, and an opposing character rolls a single die and gets a 5, the 5 wins out. None of the other dice the first character rolled have any bearing on the outcome - only the High Roll matters.
The Rule of 6
Although there are only results from 1 to 6 on the dice used in the skill rolls, a High Roll can go above 6 if there is more than one 6 rolled in a single throw. For every additional 6 rolled in a single throw, the High Roll is raised by 1. So if a character rolls five dice and gets 6, 6, 6, 4, and 2, the High Roll is an 8; 6 + 1 + 1 for the two additional sixes.
Furthermore, if every die rolled in a skill test is a 6, the player is allowed to roll an additional die. If THAT die is a 6, another additional die may be rolled, and so on and so forth. This allows for a (vanishingly small) chance that the High Roll can have any result, so even a pretty incompetent character can produce a (very lucky) High Roll of 7 or more.
The "0d" Rule
Characters who have no dice in a particular skill can still try and make a skill roll. The player rolls 1d, and subtracts 1 from the result. While this doesn't seem like a big difference compared to someone with 1d in a skill, keep in mind that the -1 modifier means the 0d skill doesn't benefit from the "Rule of 6". Furthermore, even if there is a skill modifier (due to circumstances, magic, equipment - whatever) that raises the result so the roll is a "6", a 0d skill cannot ever make use of the "Rule of 6".
And there we go. This would be the basic task-resolution mechanic for the system. There will be the occasional "roll 1d/2d and look here", and damage is done using a straight die roll, but in terms of task resolution, the "High Roll" is it.
Opinions? Comments? Questions?