Here’s a new core dice mechanic, hot off the presses: when you need to determine success, you and the DM roll 3d6. If the numbers are closer together, you succeed, if the numbers are further away from each other, you fail.
Imagine that your character is trying to pick a lock. The DM decides this is an easy skill check, so you need to roll within 6 steps of one another, meaning if he rolled a 6 and you rolled a 12, that’s still close enough for you to succeed. You and the DM roll 3d6. If you roll a 10 and the DM rolls a 12, you track the absolute difference, which is 2, smaller than the threshold for success, and you succeed. On the other hand, let’s say this was a particularly difficult lock, and the DM decides you need to roll distance 2. You and he roll, you roll a 20, and he rolls a 6, which is more than 2 away, so that’s a definite fail.
I was listening to someone talk about Dave Arneson and his original game, both system and setting, and I remember that he and M.A.R. Barker shared similar philosophies when it came to player/DM arbitration. For them, if you and the DM disagreed, you roll a d6, and the one who rolled the highest gets their way, with a compromise on the fiction if you’re close.
This system serves a couple of functions. First, because you’re more likely to roll the average on dice, there’s a lot more room for success, so it makes for a more relaxed, laid-back system. There’s a reason you move the bandit on a 7 when playing Catan, because on 2d6 the 7 is the most likely result. For 3d6, there’s something like a 66% chance you’ll roll between 8 and 13, which means there’s a greater chance you’ll succeed. Second, it’s relatively easy to determine if you succeed or fail with a quick glance of the dice. Most of the time, if you roll, see a couple of 3s, and glance over to the DM who has a 5 and 6, you know you don’t have to count it out and play can continue. However, when it’s not clear, there’s a sense where the game slows down a bit and tension builds: did I succeed? How close am I? And then the rush of success. Third, the rules mechanic can fit narratively into the setting of the game, as if you and the world are harmonizing for things to be accomplished. I can imagine a setting with lots of words like “resonance” and “synergy.” Also, rolling 3d6 means fun times on the 666, which is both the highest you can roll and also only showing up on a half-percent chance. I believe this is a more explicit mechanic in Infaernum, but even Mork Borg had that scripture table where you burn the book on 7:7.
Speaking of, I imagine that this would be a good, quick mechanic for a mashup game of Ryuutama/Mork Borg. It’s not a super in-depth mechanic, especially because I think adding D&D5E style attribute modifiers would make the system a lot more clunky with players having to look at their sheet to find their modifiers and then applying them to the roll, but the setting is all about traveling at the end of the world. Things aren’t as black metal and brutal as they are funeral doom metal and sad, like ending a long journey or sharing the last sunset with a group of friends. You succeed when the world aligns just right, but more and more you fail because you’re out of sync, out of alignment, out of touch, and the world you lived in is passing on and you need to as well. (Also ironic that Ryuutama, a Japanese iyashikei game about traveling, contains more rules than the blacker than black metal Mork Borg.)
If you wanted a bit more complexity, you could assign a theme to the high and low numbers. For example, if high numbers were civilization and order and low numbers were wilderness and chaos, the way a player solves a problem could be modified depending on where the numbers land on the scale. Imagine a player says “I want to open this door.” A success on a high number (“We both get 16,”) is order flavored (“You mechanically and orderly pick the lock,”) and a success on a low number (“We both get 3,”) is chaos flavored (“You light the door on fire,”).
If you and the DM roll the same number, that’s likely some kind of critical success, being exactly in line with the universe, and if you roll the exact opposite (the player rolls 111 and the DM rolls 666), something really bad happens and you can’t talk anymore because you’re dead, Black Leaf.
I’m sure this could use some more mechanical meat on the bones, but I thought it was neat enough to mock up.