Steep is an awesome concentration game. Like a simpler, browser-based Race the Sun. Using your arrow keys, you control your ball. Use ramps to jump high over obstacles or to skip over tricky ledges. If there are no ramps, you'll have to balance between avoiding both stationary and moving blocks while staying on the narrow path.
It's super fun and easy to learn but can take a great deal of practice and concentration to get past the initial stage. No tutorial is needed, and the progression-based difficulty is much appreciated by this old-school gamer.
Highly recommend trying out this challenging - yet addictive - game! You won't regret it - though you may find that an hour or two passes by in the blink of an eye!