The Moonstone to open the Sphinx is in Vince's bag at Giza. You have to call him on your cell phone to distract him.
How to get there :
Go to the Mountains of the Moon and get the cellphone from the cave at the top. Go to Blue Nile Falls and get the Egyptian Lily, and swap it for a turban at Nabooti. Go to Giza and wear the turban to get a shovel. On the shovel there will be Vince's phone number (555-6789). After you talk to Vince, call him to distract him from the knapsack. Put the Moonstone into the ring atop the Sphinx, which will open the sealed door.
To find the sphinx stone on Nabooti Island in Poptropica, you need to climb up the pyramid and solve the puzzles in the tomb. The stone is located inside a hidden chamber, and you must complete a series of tasks to obtain it.
You can find the offering to Hades on Mythology Island in the graveyard. Look for a small statue or object to interact with as an offering.
The moai, large stone statues, can be found on Easter Island, also known as Rapa Nui, a remote island in the southeastern Pacific Ocean.
To find the magic thread on Mythology Island in Poptropica, you must first buy the golden apple from the Tree of Immortality in the Garden of the Sphinx. Then, trade the golden apple to Hercules in exchange for the magic thread.
To get the key in Mythology Island, you need to first go into the Garden of the Sphinx and find a vase with a hidden key inside. Drag the vase to the edge of the screen, then click on it to get the key. This key is used to unlock the padlock on the chained door in the Garden of the Sphinx.
The ring you need is the Nose Ring from the beastly Minotaur, whose lair is to the left of the Garden of the Sphinx. You will need the reed pipe (flute) from the Garden of the Muses, which is to the right of Main Street. Play the 8 colored notes in order and the door will open (blue blue green yellow yellow red blue green). (see related question)
On top of the Sphinx in Nabooti Island, Poptropica, you put the stone you find in the man's bag by the tent.
There are no keys on Nabooti Island. The Sphinx at Giza is opened by the Moonstone that Vince and the tomb robbers have found. It is placed in the ring atop the Sphinx. (see related question)
You aren't actually in a pyramid : you have entered the Sphinx. Defeat the four challenges to find the Green Jewel of Nabooti. (see the related solution below)
you dont need to find it it is already on the thing
You have to get past the tomb robbers and enter the tomb under the Sphinx, where you will find the Blue Jewel. (see the related questions)
There is no journal on Nabooti Island. But there is a ripped part of a journal that you need to find on Shark Tooth island.
The Kaya Forests are a location on the island, one of the spots to find a hidden Nabooti jewel.
you have to find all of the jems!
Once you have beaten the Sand Room in the Sphinx tomb, continue left through the passage to the Falling Blocks room, and you will find the exit. Anywhere else, just retrace your steps backward through the Sphinx. (see related question)
On Ghost Story Island and Nabooti Island.
it is in nabooti island
In the museum as you first enter the island. Go to the Nabooti totem pole and accept the challenge.