Redbox Hack

From the introduction: Welcome to the second edition of The Redbox Hack. What started out as an attempt to boil down the elements of red box D&D I found entertaining has turned into something with a life of it's own. You don't have to squint too hard to see some of those original D&D elements here. Classes, levels, and a system that revolves around killing monsters survived the hacking. But there's a lot of indie-game sensibilities in here too.