Second rate real-world rip-off

We climb to the top of the pyramid to rest for the night.
While on watch Bael and Rob see the apes jumping around again, but note that none of them come to the sides of the buildings facing the pyramid.  On Amber’s watch she sees a figure scale the other pyramid. Just before dawn a flock of bats fly away from it, but no sign of the human.
Isis attempts to heal the sick, but something prevents Morgan from feeling any benefit. He looks ruefully at the empty potion bottle in his hand then flings it over the back of the pyramid with a curse.

We decide to scale the larger pyramid. As we climb the stairs we see that there are streaks of old, dried blood down them and as we approach the top we see the blood stains become more widespread until they cover the top few steps.  At the top, there is an altar totally discoloured with dried blood – what sort of people lived here!!
This pyramid has no pit in the centre but it does have the same low structure with three ‘rooms’ we explore and begin to search for secret doors. Eventually, a trapdoor is found in the middle room. No one is too keen to explore this one just yet and then Bael ponders if there might be a similar one in the smaller pyramid. We rush back to check.

Indeed, another trapdoor is located. Everyone is feeling a bit braver so we open it. Handholds descend into the darkness. Minerva goes first and we follow in single file…
The handholds lead to a short set of stairs and a winding passage that takes us further into the pyramid. Eventually we get to a corridor with some archways. Something glints in the first one. Closer inspection shows it to be a glass vial in the hand of a skeleton. It’s other hand hold a stained dagger. Other skeletons sit around the edge of the small room.
Another archway is bit further down the passage. In there are more skeletons and a pile of hammers and chisels and other stoneworking tools.
A third archway has even more skeletons.
We surmise that these might be the original constructors of the pyramid, trapped so as not to reveal it’s secrets. Morgan checks and some have evidence of stab wounds and the stained dagger proves to be marked with dried blood.
The passage continues past a pair of hideous, demonic statues in niches, and then another pair. Minerva is made of stern stuff and her stoic attitude gives heart to the others. After the four demonic statues, there are a pair of statues of lion headed women with spears. The passage ends at a room with a sunken floor and a pool of acrid smelling liquid.

A copper coin confirm that it is acid. We are stuck. Amber considers using the statues to create stepping stones and tells Morgan to shift the first one. It moves and reveals a small passage behind it at the back of the niche. We shove Rob down there with Minerva’s sword of continual light. He finds a long, narrow room with sand on the floor and a mirrored wall at the far end.  He sees himself receding into the distance – the wall he entered through is also mirrored.
The sand proves to be about 2 inches deep. Rob brushes it away to check for traps as he advances. He makes his way to the far end without mishap, and indeed with any indication of another exit from this room.