Hydra has green skin, sharp (magical) spines and teeth, thick lips, and a menacing glare. Its skin is covered with scales, even though it looks smooth, like a frog's.
The Hydra is located in its cave, which is an underwater area in the realm of Poseidon. To get there, you must swim through an underwater cavern. When battling the Hydra, each one of its heads will rear back and plunge down towards you. When that happens, jump and land on them. This will knock them out. There are five heads and you must make sure all of them are knocked out. After that, click on it to retrieve its scale.
- In Greek Mythology, the Hydra has 9 heads and lives in a swamp, in contrast to the Hydra in Poptropica, which has 5 heads and resides in an underwater cave.
- It is similar to Cerberus in a few ways. Both are found in Mythology Island, both have multiple heads, and both have to be put to sleep in order to obtain an item from their respective bodies.