The Dark Forest
Where you wake. A shard, a pit, a boulder, and a forest that opens and closes on its own time.
Deep in a dark forest you find your first shard and learn to throw your head to move a boulder and escape. Nothing here was built. The way is barred by Knotwood, a single living growth whose gate and trigger are parts of the same body, and choked by Luxbushes that swell shut in the dark and shrink away from light. Overhead drift the glowing spores of the Dandelumion, the only real light the forest has.
Everything here runs on a clock. Knotwood snaps open and relaxes shut, Luxbush withdraws and grows back as the light fades, and the spore shoals pass on their own currents. The region's lesson is to read a rhythm and move on it. The tutorial of interacting with the world.