How much would interlopers who did not get that Darkwalker dream be likely to end up learning from word-of-mouth about the dream itself, and about the actual abilities it gave anyone who got it? I've been assuming knowledge about feats might be patchy based on how much the character's personally seen and who they know, but with this one it seems like people who got it might be intentionally secretive about it. Is this something NPCs might know about and talk about openly, or are we playing it cool until someone who does have that feat picks the worst best time to show off and use it?