OneDice, 1PG, XPG, and Risus. All of them very serviceable, for more than a one shot even.
I've spoke before about OneDice. I really like this game. Its got that just right about of crunch, but still very light. Where as Risus sometimes seems to lite to me. Don't get me wrong its a fun little game. That I have run, and would run again. !PG/XPG is a great game as well. Very underrated in my opinion.
But back to the question. A poster on the forum gave the best answer I have heard/read. Your favorite. That totally makes a lot of sense. Your familiar, you know its ins, and outs. Plus if your group is also familiar, which if they are your group and you've been throwing dice with them for a while your bound the be. Its just that much easier.
For example, probably my go to fantasy game would probably be D&D Rules Cyclopedia. I could grab any of my players, or even people that haven't played. I could totally wing it and bang out a one shot easy. I've done it.
So guess my point to all of this is keep it simple, keep it familiar. I suppose that could explain a lot of the interest, and varying games of the OSR. Some thoughts for you to chew on.
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