A couple of notes about the things I asked Legion in a chat: Angora is essentially just guessing that the "thing" is from another plane, the penin started having disagreements because they went poking at the sword with just a bit of questionable desires in their minds to begin with, and the "thing" had a similar effect on them as it did on Angora, amplifying said feelings, and the "explosion of the being's escape" had nothing to do with the being, but was rather just a slight accident involving the sword's magical-energy-channeling properties ... and nightmares are still nightmares, amped further by the "thing".