Descending: The party enters the temple by descending down from a hole high on the western wall. It's not a hard climb, but requires enough focus that climbers have disadvantage on perception checks to notice the dangers within.
Lighting: Only natural light spills into this room from the hole on the wall. The ceiling on the far side of the room is concealed.
Bats: When crossing the room, if the party isn't VERY quiet, they rouse the nest of bats on the ceiling. The bats fly about frantically, granting concealment to the 3 Giant Bats that are among the swarm. If two of the Giant Bats goes down, the other one flees, the other bats following close behind.
Hidden Treasure: Underneath a loose floorboard in the northeast corner of the room is a small wooden coffer, it's iron lock rusted over. Inside is your choice of treasure (coins, gems, maybe one or two potions that may break if the box is smashed open). The box belonged to a former Temple Priest, and he may have personal belongings in there, such as letters, a gift from a loved one, or a family heirloom. Give it some flavor!
Room 2 – What's in my Closet?
Doors: The wooden double doors to this room are ornately carved with detailed designs, with the insignia of the deity formerly worshiped here on the center of each. They are unlocked, and creak loudly when opened.
Lighting: With the door open, some natural light may spill in, providing dim light to the small room.
Closet: On the north wall is a short (5ft) but wide wooden door with a cobweb-covered iron lock on it. The lock is slightly rusted, but still functional, and can be picked with thieves' tools. Inside the closet are old, dusty robes. The ceiling here must have a leak, because some of the robes have a dark black mold growing on them. A character that searches through the robes must succeed on a Constitution save or be poisoned for 1 hour.
Tapestry: Taking up nearly the entire south wall is a great tapestry depicting an avatar of the deity guiding his disciples and casting out their enemies. The tapestry is made of a rare fabric, and would fetch a hefty price from historians or collectors.
Room 3 – Devout Worshipers
Door: The door here is wood and plated in copper, that has long since oxidized into a dull green. It is unlocked.
Lighting: This room is completely dark.
Worshipers: Some of the deity's more devout followers have stuck around after death to maintain the altar. Depending on the desired power level, these can be zombies, skeletons, ghouls, wights, or some other form of undead.
The Altar's magic keeps the worshipers alive, but also confined to this one room. If the altar is not destroyed or the corpses not moved from the room after being slain, they will reform in 1d4 hours.
Altar: Besides keeping it's guardians alive, the altar itself is protected by protection magic. Living creatures that come within 5 feet of the altar must succeed on a Constitution saving throw or become paralyzed for 1d6 minutes. The altar can be destroyed physically.
Treasure: Inside the altar is a magical item of your choice, though it should be connected in some way to the deity. A preferred weapon, or weapon of an enemy, or a totem or symbol of some sort.
Room 4 – Hidden Secrets
Door: This wooden door is plain and unlocked.
Lighting: This room is completely dark. Light sources also have their distance and effectiveness decreased by half (20 feet to 10 feet, bright light to dim light, etc.) due to the thick, ashy dust that hangs in the air.
Bookshelves: The eastern wall is lined with musty books on crumbling wooden shelves. One of the books hides a key, locket, or some other important or interesting item.
Room 5 – Deals with the Devil
Door: This solid wooden door is reinforced with iron bands, but time has taken its toll. Still, the lock holds tight, and it will require some work to open.
Lighting: A lone candle burns forever in the Northwest corner of the room.
Ritual Circle: Before his death, the high priest attempted to make direct contact with his deity, but instead summoned a sinister force from the far realms. The Creature here (demon, slaad, genie, or some other intelligent outsider) is cunning, but thirsts for battle. He challenges the party, promising them a gift if they win. He is true to his word, and if beaten (make it so he stops after falling below a certain threshold) he will grant a magic item, powerful boon, or important piece of information to the party. He then fades back into his home plane.
Desk: The crumbling remnants of the high priest's large desk sit near the north wall. Inside the party finds nothing but a rat nest and bugs. This is a great place to put a macguffin, or a story device.
