Rosewood's Call

A contact person, called Kiruko, has located a shard of the bifrost, a precious artifact you're after. They've sent your troop to Saint-Geldar.
Saint-Geldar has a couple of noteworthy buildings:

The portal.

Standing central to the village is a large portal. It however requires an activation stone of the desired location.

Geldar's altar.

The unholy Saint-Geldar's final resting place. When pressing his head on the altar, a portal stone to a Balor's hold will appear out of the altar.

The Burnt Umber Tavern.

A tavern run by the tiefling family of Zandori. It's mother, Tina, runs the place and is behind the bar most of the time. Here the adventurer's can find a note left behind for them.

"Duties permit me not to be there with you at this time. But I have hidden a teleportation stone for the portal in the center of town.
Go to where this town's faith lies and press at it's feet."

• Inside is Phesaek, a Kalashtar that's trying to work against Kiriko. She has long black and white dreadlocks and will help the party if they convince her they also want to turn on Kiruko. She will do this by giving asking them to join her as she has a portal stone to Nessus, the capital, but isn't strong enough on her own to defeat the Balor guarding the exit portal.
• Tolki, a small halfling tinkerer. He usually runs Tolki Tinkies but is more often inside the tavern instead of the shop. He is very enthousiastic and will try to sell the adventurers anything, especially his line of walkfasters: "a wheel attached to a walking cane." He is in favor of the Empress but is not bothered by politics much.
• A group of fire genasi soldiers.

Senki's Irons.

A smithy run by an Azer called Senki. He knows of the tale that was Hel before it was called that.
the tale

"Before the lady Hel claimed the lands it was a plane of pure fire, mountains of flames and lands of ash, the rivers were lava and the boats were brass. The air, thick and nurturing with heat. But then the Lady Hel claimed the fiends, dominating them under her rule. This allowed people of ill will, like Kiruko, to abuse fiends and enslave an army. It was better in the olden days, where the spirits were passionate and free. Full of flame. The passion has died with the half faced queen."

When pressed about the issue, he will direct them to the Kalashtar sitting in the Burnt Umber.

Flicker's home.

Flicker is an old fire spirit (Myrmidon). Flicker is old, almost fading. He will be watching from his window most of the time. Speaking in murmurs and being very disoriented. When mentioning Kiruko, he will stand guard.

Hel's temple.

A house dedicated to sacrifice, here serves priestess Raya (an Erinyes). She will perform sacrifices in the name of the empress of the dead.

Tolki Tinkies

A very active halfling called Tolki runs Tolki Tinkies, he will be in The Burnt Umber Tavern normally. Otherwise he might be in his shop.

Ending

At the end they fight a Balor.