Lonely Mountains: Downhill is an upcoming third-person mountain biking game with a minimalist direction in more than just its art style. There are no fans or structures along the mountain roads, just you, the trees, and the wind in your polygonal hair. It looks like a rad combination of a relaxing nature ride and an Xtreme downhill run (specifically with a capital X and no E).
As you scream down the mountainside, you'll be able to run races and time trials, which will connect to online leaderboards and may even let you race against your own ghosts. There are also hidden areas to find and lots of natural jumps to go off of, so it seems to be as much an exploration game as it is a blocky rendition of downhill biking.
The game will apparently let you ride from the very top of a mountain to the bottom without any load screens, and won't have restricted paths you're required to follow—so if you decide careening off a cliff may be a better route than the beaten trail, by all means go for it. But as the trailer shows off, crashing and ragdolling off your bike isn't out of the question either. With one of the stated features being that you'll travel the world, I imagine finding the best routes (and probably a lot of bad ones) down each mountain is all part of the fun.
Lonely Mountains: Downhill is hoping for a "early/mid 2018" release and just hit Steam Greenlight. You can vote for it here if you like the look of it as much as I do, and can also learn more on its official site.