Pulcra Vermis:Re

Pulcra Vermis:Re is a first-person puzzle exploration game with elements of psychological horror. In the game, an unfortunate adventurer finds himself trapped in a strange dimension in which stands a colossal castle, inside, in order to leave he has to resolve multiple puzzles while deciding whether to listen or not to a mysterious voice in his head. 

The game has 3 endings.

https://paragonearth.itch.io/pulcra-vermisre

Source: itch.io