get the five sacred items, give them to Zeus, go to Hercules, and use the mirror to get there.
You cannot open it until you have the aid of Hercules, and he will not do so right away. Once you have all 5 sacred objects, you have to bring them to Athena at the Tree of Immortality, where their message can be revealed. Then they will be stolen by Zeus. Now Hercules will agree to help you, and he can move the boulders blocking you from Hades and from Poseidon.
Hercules is not going to help you during the hunt for the Five Sacred Items. It is only after Zeus has taken them from you that he agrees. His contribution is to move the large rocks blocking you from the throne rooms of Hades and Poseidon, and to open the lock on the Olympus gate. You will need the Touchscreen Mirror from Aphrodite's test on the beach in Poseidon's realm. (The answers to her test are Ares, Hermes, Aphrodite, Artemis, and Hestia.)
On Mythology Island, you will meet the god Zeus, and his daughter Athena at the Tree of Immortality. You will find Aphrodite on the beach in the realm of Poseidon. The gods Poseidon and Hades are in their throne rooms, which you cannot enter until you have recovered the 5 sacred items and returned them to the Tree of Immortality.
To get Hades's offering, you go to the garden with the spinx statue. You then find a pomagranate tree and pick them. Those are the offerings.
In Poptropica's Mythology Island, Hades' throne room is located in the Underworld, which is accessed through the entrance in the Tree of Immortality. Once you navigate through the challenges in the Underworld, you will reach Hades' throne room where you can defeat him and complete the island quest.
You get it in Hades palace for cleaning graffiti for a worker in the throne room.
Place it on the offering stand in Hades throne room.
Hercules will not help you until you have collected the 5 sacred items and had them stolen by Zeus. You will need the Touchscreen Mirror from Aphrodite's test on the beach. Transport yourself with Hercules to the Hades door and he will roll back the big rock. He will do the same for the rock blocking Poseidon's throne room.
herculees does that
Hades is in the underground
You do not break through either rock blocking the throne rooms to Poseidon or Hades. You must first return to the Tree of Immortality with the five Sacred Items. You will need Hercules, but he is not willing to help you until then.
The Temple of Hades is in the Grove of Temples. You will need the Pomegranates from the tree in the Garden of the Sphinx (far left of the island). Place them on the altar and go down into the abyss, and cross the River Styx to find Cerberus and the Hades Throne Room.
On the island
Mythology island :)
You can only enter the throne room of Hades when you have Hercules with you. That cannot occur until after you have collected all five Sacred Items and had them stolen from you by Zeus. Then Hercules will get you in to see Hades, and also Poseidon.
Hercules is not going to help you during the hunt for the Five Sacred Items. It is only after Zeus has taken them from you that he agrees. His contribution is to move the large rocks blocking you from the Hades and Poseidon throne rooms. He also smashes the lock on the Mount Olympus gate.