So some of my initial thoughts about my game is that OF COURSE characters have the classic six attributes. These will potentially range in score from 6 to 20, depending on your character's race and what you roll during character creation.
The basic mechanic will be: have a Success Score that you are trying to get equal to or below on 2d12. Generally that Success Score is going to be a relevant ability score. Getting a double 1 is always a success, getting a double 12 is always a failure.
I'm going with the name 'Success Score' right now but I don't know if I like it. I don't want to use something like 'target' though because that feels counterintuitive to how the rolls work. I'd expect the higher a target number is, the harder something is to do. Whereas here the higher the number, the better your chances are of succeeding.
Something else I'm pondering is the idea of partial successes. I really like that element of Dungeon World, that the players often get to kind of get what they want but have to accept some sort of compromise or caveat. Obviously some systems revel in the characters being crap at stuff, but I think in general players like to be competent (just like the characters usually are in adventure fiction). But always succeeding is boring too. That's why I like having the additional layer of a partial success too. The obvious one being that in a fight, a success means you hit them and a fail means they hit you - but a partial success probably means you hit each other.
How to work that into my above plan for rolling under a Success Score though? I was wondering if it'd work to have a rule that if your total on 2d12 is above the Success Score (so normally a fail) but the individual numbers on both dice are below the Success Score, then it's a partial success.
I kind of like it, but then you have the problem that if the Success Score is 12 or higher then you're never going to fail (apart from the 1-in-144 times you manage a double 12). You'll always at least partially succeed, if not fully succeed. There's a good chance that most characters are going to have at least some attributes at 12 or higher (especially in attributes relevant to their class), so this could mean that a lot of characters rarely if ever totally fail at their core activities.
This could be mitigated somewhat by having some sort of difficulty "handicap" added to dice rolls, depending on the situation. That's how armour in combat could work for example. But is that then overcomplicating things. I like the simplicity of having people roll equal-to-or-under their attribute scores for most actions, but if I'm going to stick with that then I may have to give up on the idea of partial successes.