1. An entry area for submersibles that balances pressure to enable human (and equivalent) passage. Closes behind them and cannot be opened from the inside. Attempts to open from the inside using the button labelled to the effect will result in the release of bloodlike chemical into the surrounding ocean to summon carnivorous sea creatures, which will then be allowed into the pyramid via small holes (too small for a submersible) as the water level is allowed to rise.
2. The treasure room. The huge hoard of treasure looks beautiful, but is in fact entirely fake and coated in poison. A number of artefacts and wall fixtures will result in the springing of the deadliest trap, whereby the pyramid opens to flood itself with water, the false ceiling of the treasure room opening and killing intruders by drowning, pressure, or impact with the spikes that suddenly emerge from every wall. A grated floor slides across the entry tunnel, reducing the intruders to chunks for easy consumption by the creatures mentioned in 1. Attempts to bypass the standard entryway by tunnelling through the pyramid will similarly respond in guiding the intruders to the treasure room (by way of traps of increasing difficulty in that direction) and then springing the trap.
3. The gallery hall up from the real entrance, which is accessible from the underworld waterways of Osiris. That doesn't make it safe though, it has traps for days, starting just after the entrance to room 5. Each of the traps has a riddle that reveals the method of disarming them, except the 4th and 13th traps. Each trap disarmed also quietly re-arms the trap behind it, which cannot be disarmed in the same way for 1 hour. The 4th trap has no riddle, while for the 13th the method to disarm the trap has no relation to the riddle at all. The riddle for the 1st trap is fairly straightforward, thus luring people in that direction rather than exploring the other direction.
4. The fake tomb. Extremely richly decorated in gold and gems, which can distract some from the fact that the ceiling is covered in spikes. Any attempt to move or disturb the sarcophagus or walls seals the door and causes the entire room to invert. After a few seconds, the room will invert again, also dropping the spiked ceiling (there's a gap in the spikes for the sarcophagus). As the ceiling slowly winches back into place, water and sea creatures will be allowed in to clean up the blood and eat the remains, so the room looks undisturbed for the next trespasser.
5. The true tomb. The entrance is a stone slab carved with a prominent owl design, and in front of it is a trap door that is not very difficult to detect. Atop it is a lever labelled "Push to open". Pushing the lever down will open the door to the tomb. Any attempt to interact with the door itself will activate the trap door below and also cause the section of floor behind to drive upwards into the ceiling. Within the true tomb appears to be very little - standard wall paintings, and no real treasure to speak of, other than the somewhat drab sarcophagus in the centre. The first attempt to open or move said sarcophagus will cause the floor to flip upside down, tipping the intruders into a pool of a similar kind to Lake Natron. Closer inspection reveals switches on the sarcophagus, but all they do is cause several-second delays to the trap. Were someone to successfully open the sarcophagus, they would find a hole with very slippery sides leading down into the pool, with the words "Ever considered mummification? Inquire within." carved on the inside of the lid.
On the other hand, ignoring the sarcophagus and inputting a password using the hieroglyphs on the walls will cause a fake panel to slide out revealing some of the sacred treasures of Osiris, such as the Violet Jewel of Atum.
Thus, for someone from Osiris to access the treasures, all they have to do is go up the tunnel, push the lever, input the relevant password and huzzah. For everyone else though, it would be a bit trickier.
