How I turned D&D’s Death House into a Doctor Who-style time loop

A few months after my Dungeons & Dragons players wrapped up Waterdeep: Dragon Heist, I set them on a new homebrew adventure outside the city limits for an arc I casually dubbed Uncharted. Far to the east, a massive column of green light burst into the sky, plunging the continent of Uta into an endless night full of deep fog. The “Anomaly” of light transformed Uta into a Domain of Dread from Ravenloft — but don’t tell my players that. Many of the maps, mechanics, etc. they’ve encountered in this arc were adapted from Curse of Strahd and Van Richten’s Guide to Ravenloft.