Ratskinner
Adventurer
I'm a little unclear as to the motivation for this exercise. Are we trying to promote rpgs to a newcomer? Just looking for a clear(er) game? How are you counting mechanical complexity vs. long lists of elements (spells, weapons, etc.) vs...etc.
I'd actually argue against most Powered by the Apocalypse games for clarity of writing. I don't actually find them particularly clearly written at all, especially for the GM position. IME, they tend to presume an audience that is somewhat either vested in rpg theory or already familiar with Apocalypse World itself. Which isn't to say that I don't have a growing collection of such games, but I just can't see how they fit the criteria in the OP. Although they are easy to play, once you get to know them, trying to explain how that works is a different manner. (YMMV, of course.)
In part, I think many d20/OGL games suffer from this presumed familiarity as well. However, simplicity is your friend, here.
Honestly, the 4e rules are very clear for d20 games, functionally. If you can find a copy of them. (and the "fixed" skill challenge rules.)
I haven't read every recent set of rules, or even every book that uses them, but...
The Fate Core rules are very clearly presented with (at times) almost too much detail and explanation. The size of the book, and amount of text might make it seem more complicated than it is to actually run or play, but the detailed text helps it to easily stand alone for clarity. (And the text is fairly plainly written as well.) ...but the weird dice.
Its very specific to genre, but the Gumshoe system games that I have are pretty good at explaining how they work without getting too lost in theorizing. I would lean toward Esoterrorists, even though I think Night's Black Agents is an overall better game, because NBA is wrapped with a ton more detail and world-specific info.
I'll toss some oddballs out there too:
Risus, and or PDQ, if you are willing explain the basic structure of rpgs. They're just too simple to get wrong, but they skip the "what's an rpg?" explanation.
Old School Hack, one of the best little weird D&D sorta-clones I've ever played...too bad it kinda died on the vine.
Anyway, I hope that helps.
I'd actually argue against most Powered by the Apocalypse games for clarity of writing. I don't actually find them particularly clearly written at all, especially for the GM position. IME, they tend to presume an audience that is somewhat either vested in rpg theory or already familiar with Apocalypse World itself. Which isn't to say that I don't have a growing collection of such games, but I just can't see how they fit the criteria in the OP. Although they are easy to play, once you get to know them, trying to explain how that works is a different manner. (YMMV, of course.)
In part, I think many d20/OGL games suffer from this presumed familiarity as well. However, simplicity is your friend, here.
Honestly, the 4e rules are very clear for d20 games, functionally. If you can find a copy of them. (and the "fixed" skill challenge rules.)
I haven't read every recent set of rules, or even every book that uses them, but...
The Fate Core rules are very clearly presented with (at times) almost too much detail and explanation. The size of the book, and amount of text might make it seem more complicated than it is to actually run or play, but the detailed text helps it to easily stand alone for clarity. (And the text is fairly plainly written as well.) ...but the weird dice.
Its very specific to genre, but the Gumshoe system games that I have are pretty good at explaining how they work without getting too lost in theorizing. I would lean toward Esoterrorists, even though I think Night's Black Agents is an overall better game, because NBA is wrapped with a ton more detail and world-specific info.
I'll toss some oddballs out there too:
Risus, and or PDQ, if you are willing explain the basic structure of rpgs. They're just too simple to get wrong, but they skip the "what's an rpg?" explanation.
Old School Hack, one of the best little weird D&D sorta-clones I've ever played...too bad it kinda died on the vine.
Anyway, I hope that helps.