Marble Run taps a delight that goes all the way back to childhood: a rolling marble, a track full of slopes and drops, and the quiet thrill of watching physics do its thing. As a puzzle game, the fun is in the setup, reading the layout, judging momentum, and coaxing that little sphere exactly where it needs to go. Gravity does the work; your job is to make it cooperate.

There's a hypnotic, tinkering satisfaction to this genre that a lot of louder games never reach. It's free and browser-based, ready for a calm few minutes or a stubborn go at a tricky descent. Get the angle right and the payoff is pure. If you enjoy this hands-on kind of thinking, there are more puzzle games to roll through.