Hydra

The Main monster from the 2009 movie, Hydra: The Lost Island.

Background
The Hydra lives on an uncharted deserted island. When four archaeologists find the island, they decided to check it out. There, the Hydra kills and eats three of them while the last one runs off, but is trapped on the island when the ship that they had used sunk. When a rich man uses the island for a manhunt, the Hydra devours his porters and his customers when they land on the island. The people who were being hunted manage to find the archaeologist. She tells them that the only way to kill the Hydra for good is by using the magic sword of Hercules to cut off it's heads completely. While one of them gets the sword, the archaeologist sacrifices herself to give them time. When the characters manage to get the sword, one of them cuts off all the heads. However, the last head didn't get cut off completely and it heals. It gets on the ship that they were on and devours the rich man and his wife as just a one-headed Hydra. The remaining characters manage to cut the last head completely off, causing the body to disintegrate and carry the sword of Hercules away, killing it for good.

Powers/Abilities

 * Vision: While not physically shown, one of the characters states that the Hydra can stalk it's prey with heat and movement like a snake.
 * Head Regeneration: Just like in the original Greek legends, the Hydra can regenerate it's cutted-off head and gain a another head.
 * Healing: This Hydra seems to have the ability to heal itself quickly when it's last head wasn't completely cut off.

Kills

 * Panos: Legs bitten off and devoured off-screen.
 * Shin: Torn in half from the waist.
 * Dr. Kim: Torn in half from the waist and each half is eaten.
 * Horst: Torn up into four pieces
 * Otto: Torn apart and gets eaten alive.
 * Knut: Gets body bitten (off-screen)
 * Gunner: Gets each shoulders bitten and is eaten alive (off-screen).
 * Williams: Constricted by the Hydra's necks and get eaten alive (off-screen).
 * Sean: Torn in half from the waist.
 * Broughton: Torn apart into pieces.
 * Captain Sweets: Head and left shoulder bitten off.
 * Dr. Valerie Cammon: Eaten alive.
 * Dixie Camden: Bitten at the waist and eaten alive (off-screen).
 * Vincent Camden: Devoured whole.

Trivia

 * The movie says that the Hydra can only be killed by the sword of Hercules, when really according to mythology, Hercules cut off the heads and uses a torch to burn the head stumps so it wouldn't grow more heads.