A monochrome game where a stickman chases shadows around logic-defying structures hanging in space, you say? Yeah, that'll be Echochrome. But that hasn't stopped us from loving every head-scratching minute. The first hour or two playing Echochrome was mostly spent just enjoying the novelty of its concept.
You don't control the walking/jumping/falling character as such; you control the level (or the camera, depending on how you look at it), rotating away until a path to a 'shadow' character appears - effectively a stage waypoint or goal, which is novel. How the level appears is of paramount importance, as the whole game is based around Escher-like geometric structures, so what you see is less important than how it's seen. Again, it's a novel idea. A few hours in, it becomes apparent that these fresh ideas gel together really well (like therapy and chaise-lounges, probably), offering the sort of cerebral challenge that we're tempted to describe as "the new Lemmings," if Lemmings existed in a mind-bending 3D universe."
