Sunken Catacombs of Hell Bird

After being destroyed in a great battle years ago, the catacombs remained abandoned. Currently they are infested by alligators, indifferent to the history of the place. It is rumored that the legendary staff Darchimos is still hidden here.
Hell Bird, one of the rumored Morning Stars, is supposedly buried here. According to legend, Hell Bird gave the gift of fire to mankind and trailed flames when he flew through the sky.
Legends claim that Hell Bird and his devoted warrior followers are buried here. Unfortunately, this sacred place was flooded and partially destroyed in one of the great battles of the Caninian campaign. Allegedly, both armies were racing to find Darchimos, the legendary staff that Hell Bird is rumored to have used. Neither army seems to have found it, and the catacombs remain abandoned to this day.
The catacombs were built underground. During the battle, the cliffside that the entrance was built into collapsed, causing huge boulders to block the way. This caused part of a nearby river to divert and begin falling through a hole in the ceiling. To enter the catacombs, boulders must be moved and climbed around. The walls in the entryway are covered in water and green plants from the humidity of the place. The tombs of the soldiers buried here are mostly hidden by ivy. The smell is not one of death, as one may expect, but of life and fresh water. Natural skylights have broken through here and there, providing ample light to see. Stepping through the boot-high water down the hallway, several doors and hallways branch off, many ending in dead ends. One battered iron door is locked. Large, scaly shapes lie in wait along the sides of the walls, their nostrils and eyes barely breaking the water's surface. In one large and partially dry room, a mosaic of an ancient bird pattern is painted across the entire floor. There are crates and tombs scattered about, full of gold, gemstones, and weapons. The warriors who are buried here believed these items would help them in the afterlife of Hell, where they were destined to eternal battle with their faithful leader. In a further room, there are remains of someone apparently recently killed by ancient weaponry, with a helm and lockpicks still in his hands. In the furthest room, a giant pile of rubble hides an iron key.