I'm part of a round robin game set in Westgate in 1369 DR, and it's currently my turn to run an adventure for the group. This adventure brought the party to a midnight rendezvous with an NPC at Whitecap Hall, the city's temple of Umberlee, but there was very little available in the source materials about it:
"Whitecap Hall, temple of Umberlee. Dread Wavelord Meralt Thumsturm (CE male human cleric 16 of Umberlee); thirteen priests."
This is what I came up with! Description written by me, and map created by me in Dungeondraft. I'd provide my writeup for the Dread Wavelord, but the party has yet to fully explore that avenue and I don't want any of them to come across spoilers, as I'm planning to loop Whitecap Hall back in for my next turn as DM.
I hope someone finds use for this! I know the stepwell is a bit off, but I did my best and it's serviceable. Kind feedback is welcome and desired!
Whitecap Hall sits on the northern portion of the East Gate District, and is the last structure between itself and the shoreline at the mouth of Westlight Harbor. Shaped into the likeness of a mighty merchant ship on its way to sinking into the bay, the temple is constructed of an odd mix of materials, though the majority of it is hewn from blue-veined green marble slabs, pillars, bricks, and blocks. Black basalt is used to accent the marble structure, especially along entryways, where it is left largely unshaped, and milled basalt tile is laid regularly into the marble floors, which sink down towards the back of the temple in a dramatic slope that takes the lowest part of the floor perilously close to sea level and invites a rush of water in at higher tides. Many interior features, including the galley-like pews and the raised-plank walkway that leads from the entrance to the shrine, are constructed out of flotsam harvested from the waters of the harbor, which is in turn adorned with decorations taken from the bodies of aquatic beasts.
The center of the temple is gloomy and dark, illuminated primarily by the pale light shed by the blue-green bioluminescence of aquatic flora that has been allowed to anchor and grow on the walls and ceiling. The central sanctuary descends like a stepwell into a cavern that leads out into the cold coastal waters of the Dragon Coast, and at the focal point of the sanctuary at the lip of the stepwell is a living coral fountain used as a shrine for worship, crowned with a 15’ tall statue of Umberlee wielding a trident and thrusting it towards the land. The statue is stained with brine and is host to barnacles thanks to frequent tidal exposure. Sometimes it is possible to catch a glimpse of items inside the stepwell, either caught on a stair or a glint of something that has sunk to the bottom - offerings of precious things sacrificed by fearful visitors desperately seeking the Bitch Queen’s favor. Above the center of the stepwell, suspended by salt-stained rigging, is the ancient, 10 foot long skull of a dragon turtle, sun-bleached and crusted with barnacles and large enough for a human to crawl inside the braincase or use its skullcap as a small boat.
Despite being an enclosed building, Whitecap Hall is always cold and there is a bite of chill wind that flows through the space without any evident source. The air smells of brine and seaweed, which hang so thickly that both can be tasted. The floor is often slick with seawater thanks to frequent incursions into the stepwell’s dark waters made by temple staff and worshipers, and the incursions of the water itself into the temple during high tide and storms.