The Hydra is a varied character with experience when using eridian weapons. The Hydra can split into multiple people when using his action skill to take out large crowds. The Hydra clones battle until death or action skill time running out. Also if a Hydra clone dies, two more spawn in its place.
Eridian head tree: Improves eridian weapon capabilities.
Split head tree: Improves special ability, and elemental abilities.Arrow head tree: increases stats and healing abilities.