From The Heroes of Might and Magic III wiki

Town: Fortress

	Attack Skill	18	Damage	25-45
	Defense Skill	20	Health	250
	Speed	7	Shots	0
	Growth	1	Cost	3500 Gold + 1 Sulfur
Special: No enemy Retaliation, Attacks all adjacent enemies

[edit] Dwelling

Chaos Hydra is recruited in Upg. Hydra Pond.

[edit] Upgrading

This is the upgraded version of the Hydra.

[edit] Description

Chaos Hydras are multiheaded serpents attacking with vicious bites. When they attack, they attack all adjacent enemy stacks.

[edit] Strategy

Since the Chaos Hydras attacks all adjacent enemies, they're great in close quarters. Try getting them in the middle of enemy groups, Teleporting is good, and attack. Counterstrike can also be devastating.