The Hydra of Lerna, more often known simply as the Hydra, was a serpentine water monster in Greek and Roman mythology. Its lair was the lake of Lerna in the Argolid. In the canonical Hydra myth, the monster is killed by Heracles (Hercules), using sword and fire, as the second of his Twelve Labors.
According to Hesiod, the Hydra was the offspring of Typhon and Echidna. It possessed many heads, the exact number of which varies according to the source. Later versions of the Hydra story add a regeneration feature to the monster: for every head chopped off, the Hydra would regrow two heads.
The Hydra had poisonous breath and blood so virulent that even its scent was deadly.
Water Dragons are giant sea-dwelling dragon-like beasts. These aquatic monsters made their first appearance in Castlevania III: Dracula's Curse as the bosses of Block 6A, Causeway of Chaos. As with some other enemies in this game, both their design and attack patterns differ between the original Japanese version and the Western localization.
They reappeared later in Super Castlevania IV, where they were called the Orphic Vipers. This variant waves both of its heads continuously and each has a distinctive attack of its own: one breathes a short-ranged flame and the other spews three-directional fireballs. Although referred to as two different monsters in the Western localization of Super Castlevania IV (probably referencing the dragons from Dracula's Curse), in the Japanese version it is called Twin Head Dragon, confirming that it is in fact a single creature with two heads.
A single-headed aquatic Serpent appears as the harder alternative to the boss of the first stage in Castlevania: Rondo of Blood. In the remake, The Dracula X Chronicles, it largely reprises its role from the original, although another variant called the Hydra is present as the boss of Stage 5'.
A version of this creature with arms appears as the first boss of Castlevania: Legacy of Darkness, actually being the responsible for sinking the ship Cornell was traveling on. This Water Dragon also makes an appearance in Castlevania: The Arcade.
An icy water dragon called Rahab first appeared in Akumajō Special: Boku Dracula-kun. It was later mentioned in Castlevania: Symphony of the Night, where the Icebrand sword was referred to as "Rahab's Sword" in Japan. The sword was also called by this name in Castlevania: Aria of Sorrow and Castlevania: Portrait of Ruin. This great aquatic beast made its second boss appearance as a more fish-like creature in Castlevania: Dawn of Sorrow. Some of its attacks would cause a brittle ice bridge over the surface from which one could step on and fight back at the creature.
|Enemy Data: Sea Dragons|
|Image||Name - Game|
|'|| 6A. Causeway|
|'|| 4. Ice|
|'|| 3. Cavern/Waterfall/Moat|
|'|| HP: 92|
| 1. Village|
|'|| 5'. Sunken City|
| HP: 200 (320 Hard), 0 for spit|| Foggy Lake|
|A monster that dominates the seas.|| Strong: Water|
Weak: Piercing, Electric, Holy
| Soul: Deep Seeker|| Subterranean Hell|
|'|| HP: 92|
Exp: 1,000 × 5
| 5'. Wandering|
|The dragon was always top of food-chain (sic) before the dawn of humanity. All the other beings are only fodder for them. Of course, humans are no exception.|| 3. Underground Waterway|
|Super Castlevania IV|
|Simon Belmont - Dracula|
|Rowdain - Medusa - Orphic Vipers - Puwexil - Koranot - Dancing Specters - Sir Grakul - The Monster|
Zapf Bat - Akmodan II - Slogra - Gaibon - Death
|The Drawbridge, The Fortress, The Stables - The Forest, The Poison Lake, The River|
The Caverns, The Waterfalls, The Moat - The Outer Keep - The Castle Court - The Halls - The Unliving Quarters
The Dungeons - The Treasury - The Clock Tower - The Castle Keep
|Theme of Simon Belmont - Akumajo Dracula Best 2|
|All About Akumajo Dracula - Famitsu Akumajo Dracula - Nintendo Power Super Castlevania IV Guide|
|Bestiary - Inventory|
|Castlevania: Dracula X|
|Richter Belmont - Annette - Maria - Dracula|
|Keruberosu - Myotia - Dyurahan - Minotaurusu - Ghost - Lypuston - Salamander - Carmilla - Death|
|Burning Town - Gate and Entrance to Evil Castle - Great Hall - Clock Tower - Count Dracula|
|Dungeon - Courtyard|
|Caves - Stage 5'|
|Divine Bloodlines - Dracula Music Collection|
|Bestiary - Inventory|
|Castlevania: Legacy of Darkness|
|Foggy Lake - Forest of Silence - Castle Wall - Villa - Outer Wall - Art Tower - Tower of Ruins - Duel Tower - Tower of Execution - Tower of Sorcery - Room of Clocks - Clock Tower - Castle Keep|
|Castlevania: The Arcade|
|Vampire Hunter - Lady Gunner - Little Witch|
|Death - White Dragon - Dullahan - Minotaur - Water Dragon - Were Wolf - Harpy|
|Ruins - Palace - Underground Waterway - Ramparts - Clock Tower|
|Akumajō Dracula Best Music Collections BOX|