Koshin StudioKaeru Sekai (Returning World)
Plant seeds of light in a world that has lost its color.
When the green returns, let people settle and watch 100 years go by.
Free. Runs in your browser on phones and computers, no install or sign-up. The few buttons are labeled in Japanese, but the game is played by tapping the ground and looking around. “Kaeru Sekai” (還る世界) means “the world that returns.”
How it plays
The first view is gray: grass and trees have withered. Tap the ground and a seed of light falls, and green spreads from there. You have 10 seeds. Where you plant them changes how fast the world recovers. Even after the seeds run out, the edge of the green keeps creeping outward.
When the green is back, you choose how many people will live there. With few, houses and fields multiply, roads connect, and in time a church or a tower rises in the middle of the village. At night the windows light up. With too many, the green is worn away and the land turns gray again. How many it can hold is for you to find out.
A world from a number
Each world is generated from a number between 1 and 99,999: valleys, meadows, fjords, deserts, islands, volcanoes, archipelagos and snowfields. The same number always makes the same world, for anyone. Send a link with the number and a friend can play the same world. If you pick nothing, you get the world of the day.
Sometimes you land on a rare one: a world in full cherry blossom, a world with a strange sky, a single rock spire piercing the clouds, a huge caldera, a land of lakes. Houses follow the land too: red wooden houses of the north, white walls with blue domes, sun-dried brick.
Walk, and take photos
Press “walk” (歩く) to walk through the world in first person. On a phone, the left side of the screen moves and the right side looks around. On a computer, WASD moves and dragging looks around. Grass sways in the wind underfoot, and people come and go in the village.
Get close to a house and you can go inside: a fire in the hearth, a dining table, jars on a shelf. Each house has a different number of people living in it. Press the shutter to keep the scene as a photo.
How it is made
Everything is computed and drawn on the spot. The terrain is built from layered noise, with mountains, inlets, dunes, plateaus and craters shaped differently for each kind of world. Each pixel of the ground gets its color from height, slope and how far the green has returned. The sky is computed from atmospheric scattering, clouds drift, and water reflects its surroundings.
So that it runs on phones, the level of detail drops automatically depending on the device’s speed. If it feels heavy at first, wait a moment and it gets lighter.