MVm has been around for about four years, and, uses a proprietary system that's actually image based at the core (or was, originally). Some of the prinicpals behind it were active in the old mirai communites a while back, as well

thou and I, my friend, can, in the most flunkey world, make, each of us, one non-flunkey, one hero, if we like: that will be two heroes to begin with. (Carlyle)