What are fallen embers for?

What the title says, I’m sitting on stacks of them worried I need them for something, but if not the amassed silver would be nice to have.

They are keys to enter the “end game” system. Need one for each run.

Ah, so in other words, just sell them for money? How important are they in terms of usage vs. acquiring them would you say in your time playing it so far?

DONT sell them mate i sold mine and regretted it, you have to go out your a way to farm them manually later on at the moment from what i can tell