Having defeated the Children of the Crypt in pitched battle, the survivors pushed open the iron doors to the Hall of Heroes, and being a bit freaked out by the giant skeletal warriors, decided to backtrack a little and look around the room beyond the silver doors the Children had issued from.
There they found another couple of survivors (Cody Mazza's characters) and the bound and gagged captain of the guard troop that had gone missing in the Crypts the week before (Rumor 5). After some unsuccessful attempts to interrogate him in situ, they relented and freed him, leading him out of the room and piecing together his story. (He and his troop were sent by the Blood Prince to find the Gates of Heaven but were overwhelmed and captured by the Children before they did. The party also recovered 3 cuirasses, 3 short swords, and the royal writ from the Blood Prince to enter the crypts, as well as a velvet bag with 50 g.p. in ancient golden coins (which is a big treasure since the setting is on a silver standard).
They decided to go back to the Hall of Heroes instead of push further into the creepy children's room and investigate the sounds of singing coming from deeper within.
At the Hall of Heroes they discovered the tracks leading from the glowing golden doors at the far end, and correctly discerned that they were made by somebody walking backwards to the golden doors from the iron doors. They also noticed the pits in the floor and determined they were really really deep by throwing a piece of bone or something in and listening for the sound of it hitting bottom, which never came. They didn't actually draw any deductions from the backwards footprints, and simply tried to cross the room. They lost the guard captain and one of the survivors who succumbed to the dreadful hallucinations of the giant skeletal warriors coming to life and fell into one of the pits while fleeing. Two others who fled back to the iron doors made it safely, and were eventually coaxed to join the rest at the golden doors, making it this time.1
Pushing through the golden doors, they came to the Hall of Kings, where they found twelve empty thrones upon obsidian mini-ziggurats, and one occupied by the skeletal weeping form of Xothula, the rebellious adept of Mog'Malu. They took his crown and his star-steel dagger. Loot! They also found enormous wings, nailed to the wall and still dripping blood, that they correctly deduced must have belonged to the figure depicted in the defaced statue back in the temple with the stumps where wings would be. Finally they discovered the shimmering triangular gate at the back of the hall. After a bit of futzing around they discovered that you could pass through the shimmering field (to who knows where) if you touched your hand covered with the blood dripping from the wings to the field.2 They all elected to do this, since it wasn't a green devils face it had to be safe, right?
The found themselves transported to a platform floating in space, surrounded by stars of alien constellations, connected by a rickety looking bridge of crumbling stone to a distant spot of light. As soon as they set foot on the bridge, a gigantic writhing worm of inky darkness and cosmic filth appeared and swiftly approached the bridge, reaching to grasp them in its tentacles. They ran across as fast as they could mostly evading its grip… the two who were grabbed burned their Luck to escape its grasp before too much damage had been done and scrambled to safety on the platform on the far end. As soon as they reached it, the creature vanished and they found themselves facing their final challenge.
Lying on a crystal altar was a pale green humanoid, over fifteen feet tall, with a demonic-appearing ram's head and horns with a burning symbol on its forehead and bloody stumps where his wings had been. Quivering in terror at the foot of the altar was the Blood Prince, who the party was surprised to find alive since they had never pursued a single clue as to his nefarious plan that they had become embroiled in. Fortunately, Mog'Malu was feeling chatty, and dumped a bunch of exposition on them filling in everything they didn't know about the history of the crypts, the cult, Xothula and Mog'Malu's fall…which was everything since they never came across any of the clues scattered throughout. Finally Mog'Malu begged them to kill him and release him from his fleshly prison, which they did with the StarSteel dagger they had looted from Xothula, and after a bunch of what would have been expensive CGI they found themselves safe and sound on the beach, many miles from the crypts and the vile city of Hazruun.
fn1. Not the way this room is supposed to play out, but I simplified it.
fn2. Another place I simplified the solution.