The path
She doesn't choose the way
Nothing is explained, because nothing needs to be. Some stretches climb, some drop, most just run on. Limbo decides; she only times the jumps.
A small spirit runs and jumps her way through limbo, wherever the path leads, after a light that has never once waited for her.
Hold the left side to push her faster. It changes her speed, not which way she's going — that's already decided for her.
Tap the right side for one jump. It still lands a beat after you leave a ledge, so don't panic the instant your foot lifts.
Limbo comes with somewhere to land. Not many places, and not for very long, but they're there.
It's the only direction the game gives you. It also moves, which is the part that turns a direction into a trial.
The path
Nothing is explained, because nothing needs to be. Some stretches climb, some drop, most just run on. Limbo decides; she only times the jumps.
The light
Reaching it isn't really the point, which is the sort of thing only a game set in limbo gets to say with a straight face.
Tiny Spirit is free, and twenty-seven levels long. Limbo is finite after all.
Each level keeps your best time, so there's a reason to go back without anything to fall behind on. Play it in your browser for the current version; the App Store listing is the 2015 original. Put it down whenever. Limbo will keep.