Is there a preserve mode?

[jellyman]

Is there such a thing as preserve mode? I hate having to explore a level fully to make sure I'm not missing out on an artifact forever. I've had a few special feeling now and died on the level due to a monster I just couldn't defeat.

[Variaz]

Well, while I never looked to add or remove a preserve mode, some peoples reported finding the same artifact again after dying. So I guess artifacts are preserved.