So there is 1st ending when you

complete whole upper part of the mountain.

2nd ending when you

complete the gate-based enviromental puzzle

I would expect 3rd ending when you complete all obelisks, but once I've done it I haven't been able to find any trigger. Completing all 523 puzzles didn't help ether. Is there any 3rd ending? Are there any changes after completing all obelisks besides their color and fountains?

2 Answers

There is currently no known third ending. See for example here.

There is a third "easter-egg"-style ending, right at the start, but it is unrelated to the other tasks.

From that guide:

  • At the beginning of the game, you appear in a long tube passage. Here, you'll learn the basics of the puzzle mechanics.
  • Complete the first line puzzle, then complete the second to reach a colorful garden.
  • To the right, you'll see a locked gate with a tall pillar of bright white light.
  • Line up the pillar of light with the bright white of the sun. Does it look familiar? That's right, you can complete an ambient light line puzzle using the pillar of light and the sun.
  • Press the sun and drag down. The screen will shake and rumble, and you might have to adjust your alignment until the puzzle works.
  • Once you're able to interact, the sun is your round start point. Drag downward until the gates open, allowing you to enter the island hotel.
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