The Thing in the Portal was a being from the Shadowfell. It was probably a manifestation of the Demon Lord Orcus or one of his many servants.
Ascendant campaigns can view previous versions of their pages, see what has changed (and who did it), and even restore old versions. It's like having a rewind button for your campaign.
We've already been saving your edits, so if you
you will have instant access to your previous versions. Plus, you get a 15-day free trial, so there's nothing to lose.