Once Zeus has taken the five sacred items, Hercules will agree to help you. You will need the mirror from Aphrodite in the realm of Poseidon. Hercules doesn't like to walk far.
In Poseidon's realm, Hercules will kick away the large rock so you can reach Poseidon's throne. When you have the Trident, go with Hercules to the realm of Hades, where he will move the huge boulder. Once you have the Hades Crown, transport back to the Olympus gate and Hercules will smash open the lock.
(see related question)
You cannot get into the throne rooms (except accidentally) while you are recovering the sacred items. Take them back to the Tree of Immortality. Once Zeus has the items, Hercules will help you, providing you have the Touchscreen Mirror from the test by Aphrodite. He will let you enter the throne rooms and also open the gate to Mount Olympus.
You cannot get into the throne rooms (except accidentally) while you are recovering the sacred items. Take them back to the Tree of Immortality. Once Zeus has the items, Hercules will help you, providing you have the Touchscreen Mirror from the test by Aphrodite. He will let you enter the throne rooms and also open the gate to Mount Olympus.
When you have returned the 5 sacred items, Zeus steals them. Hercules will help you reach the throne rooms of Poseidon and Hades, and can open the lock on the Mount Olympus gate.
You can find the workman in Hades' Throne Room on Mythology Island by first completing the tasks for Hades in the other realms, then returning to Hades' Throne Room where you'll find the workman. He'll give you a key that unlocks a special room in the labyrinth.
Place it on the offering stand in Hades throne room.
You cannot open the lock to enter Olympus. After you have found the 5 sacred items and they are taken by Zeus, Hercules will help you reach the throne rooms of Poseidon and Hades, and then smash open the lock so you can confront Zeus on Mount Olympus.
You don't. Once Zeus takes the 5 sacred objects, Hercules will help you reach the throne rooms of Hades and Poseidon, and will smash open the gate to Olympus. But after that you are on your own. (You need the one drachma you can earn by removing graffiti from the Temple of Hades.)
You have to get Hercules to open it.
He will only help you once you have taken the 5 sacred items back to the Tree of Immortality (where they are stolen by Zeus). Hercules will remove the rocks from the throne rooms of Hades and Poseidon, and open the gate to Mount Olympus. (You will need the Touchscreen Mirror from Aphrodite's test on the beach in Poseidon's realm.)
After Zeus takes the 5 sacred items, you can get Hercules to help you reach the throne rooms of Hades and Poseidon. Once you have the crown and the trident, you can go to battle Zeus on Mount Olympus. Transport Hercules to the gate and he will smash open the padlock. (*before going to Olympus, you will need the drachma coin from cleaning Hades' temple)
To enter the Realm, place pomegranates on the altar. There is a tree in the Garden of the Sphinx. Cross the River Styx to reach Cerberus and get a whisker. You cannot get into the throne rooms (except accidentally) while you are recovering the sacred items. Take the items back to the Tree of Immortality. Once Zeus has the items, Hercules will help you, providing you have the Touchscreen Mirror from the test by Aphrodite. He will let you enter the throne rooms and also open the gate to Mount Olympus.
Surprisingly, the answer is "practically nothing". If you ask Hercules to help you, he ignores you. Only after Zeus obtains the Five Sacred Items does Hercules decide to lend a hand. He will move the rocks that block the throne rooms for Hades and Poseidon, and can smash open the lock on the gate to Mount Olympus. Otherwise, he is a disappointment.