Just played through your prologue a few things to mention:
- the Font of the writing that represents ancient text is a bit cumbersome to read
- would leave out the whole beginning and start directly with the brother and introduce the story of "the father somehow trough him"
- the long talk in the beginning feels for me a little bit missplaced (but maybe that is just me)
- Best moment of the game was still the "First look you get inside the valey it is impressive" - generally i like the art style although the brother looks a little bit unpolished
- the brother works a little bit slow... and it would be great if you can "start a task without him"...
- i would want to have a bit more mystery right from the start... and maybe do all "the things in place (digging, polishing, and picking)" just in one place instead of running arround from place to place... maybe on larger side (where you could do something on your onw later)
... the first nightmare was good like the atmosphere of it (just if ther would have been a real dream sequence it would haven been even cooler)... the nightmare at the end was even better (even though i expected something to happen and the brother to die)
... the dialog felt a bit "artificial too me" (maybe i could used to it over time)