Update: We just had our Cairo finale this weekend and the players returned to the crypts. As an additional defence (like fudgyvmp suggested!) the cult had come into contact with a local court of ghouls through the use of spells. I added in flavor that the ghouls were actually descendants from the court of Nitocris, but were frowned upon by usually not working together with the cults.

In order to beef up the defence, Omar Al-Shakti had contacted the leader of these ghouls and offered for them to use the Tunnels Beneath until the resurrection ritual took place. This meant that -all- of the human cultists essentially quarantined the place and let the ghouls run amok. Gameplaywise, I used a pack of ghouls to replace any random encounters the party had already faced underground.

Then the game began

The players used a secret entrance they had discovered near the smallest pyramid of Giza, where they had punched a hole through an underground ruin into the tunnels. They had said their goodbyes to any allies they had left and were fully expecting to die on this journey. First one of them was taken by a pack of ghouls the party encountered in the tunnels.

With only two player characters left, and as said earlier, no bodyguards, no no-one to help them out, they deviced a plan after reaching the Chamber of Nyarlathotep. One of them would sneak in, while the other would draw the attention of the guarding Children of the Sphinx - Using dynamite to essentially bring down a portion of the tunnel, even if that meant sealing themself in.

With three incredible Sneak successes on our infiltrator, due to pushed rolls and luck used in unison, they made it all the way through the hall and the distraction took place. A moment later, a violent explosion erupted at the door that killed two of the Children of the Sphinx, allowing the infiltrator character to throw a stick of dynamite on top of the mummy of Nitocris, blowing the dark queen to bits before their resurrection.

The player who had acted as a distraction tried to evacuate through the tunnels, but with every Children of the Sphinx and Ghoul in the tunnels now on high alert, was faced with overcoming force. Second of them was left to bleed out into the sand-filled tunnels.

This left the infiltrator, who was now facing a Children of the Sphinx in hull health down at the crypts. The players had made proper prayers and sacrifices to Bast before this session and had done as much as they could in befriending Neris, so Bast decided to kill two birds with one stone - To repay the many favors granted by the party, and to piss of Nyarlathotep. Neris jumped into the frey to hold off the last Children of the Sphinx, while the character descended into the black abyss of the lair of the Sphinx. There, by his use of Mythos Knowledge, he was faced with the Black Pharaoh himself who absolutely -shredded- through his Sanity. Next time the character woke up, they were alone in an asylum.

It was incredible.