first go into Poseidon's shrine temple thing and put the starfish on the pedestal then go through the door and you should be at a beach dive into the water and you'll be in an underwater maze. Air bubbles will give you more oxygen so pick them up often. to get to the Hydra go down and then up to the right then go down some again you should be at a fork in the path now so go left and down. keep going down until you reach a path going left continually go in a down left direction until you reach a cave and you should be there
you can't
It's an underwater cave at Poseidon's "castle"
you dive down underwater and you go into a cave
The Hydra is a six headed beast on Poptropica.
you go to the beach and there will be a sine that says gnarly monster, you go under the water. there will be bubbles .collect them to get more breath. when you are to the bottom of the sea. you will see a cave. go in to find the hydra.
you have to jump on all 5 of the hydra's heads and then click on the hydra and you will get the scale
Jump on their heads.
The Hydra is in his underwater lair. Swim out from the beach to the underwater maze, then go right, down, and left to find the Giant Pearl and the entrance to the Hydra cave.
When it tries to bite you, jump, and land on its head.
The hydra is underwater in Posidons temple/house. Once you get inside the house there is a big "pool". You can go to the one area and there is an opening. The hydras at the end of a maze underwater.
Defeat the hydra who is found in a cave in the bottom left of poseidon's water maze.
Move your mouse over the neck of the hydra and wait till it makes the pointing finger. Click