In the ice of the planet Jebble, there is a box.
It is perhaps twice the volume of a casket, seemingly impervious to the Force, and it contains a Sith Lord.
Two Sith Lords, even, though both of them would disagree with you about whether the other one counted, on theological grounds.
It does not contain Celeste Morne, who long ago died free, before she could free the woman who had once freed her.
It contains Darth Mourne.
This does not stop the rumors that it contains powerful Jedi artifacts from circulating, once it is found in the ice. The Sith are now a hundred, two hundred, five hundred, thousand years gone, after all, aren't they?
(Surely any rumors are unfounded...)
Not even the identification of the warning sigils on a plate haphazardly welded to the top of the device as being ones commonly used by ancient Sith who actually gave perhaps three-twentieths of a damn about lab safety when doing... Apparently, something called 'Sith Alchemy'... Are necessarily indicative.
The Sith inside the box will be, once she's outside it again.