Seeping spines cover the inky scales of this long, sinuous beast, its twin serpent heads writhing at the ends of its swaying necks.
A vydrarch is covered in jagged spines that secrete a fatal poison. A creature struck by a vydrarch's tail slap attack or that strikes a vydrarch with a melee weapon without reach, an unarmed strike, or a natural weapon takes 1d6 points of piercing damage and risks being poisoned. Any creature that grapples a vydrarch takes 2d6 points of piercing damage and risks being poisoned each round.
Vydrarch poison: Spine—injury; save Fort DC 24; frequency 1/round for 4 rounds; effect 1d2 Con, 1d2 Wis; cure 2 consecutive saves. The save DC is Constitution-based.
As a standard action, a vydrarch can produce a bank of fog in a 100-foot spread centered on itself. This effect is otherwise identical that created by a fog cloud spell.
The terrifying creature known as the vydrarch was originally thought to be an entirely unique creature, but in recent years, reports from sailors have hinted at the existence of other such beasts.
Vydrarchs live solely for the thrill of destruction and chaos, but what elder force could have created such a monster is unknown. Their dual heads act in tandem to destroy vessels and devour cargo, but survivors of such attacks claim that the heads can act independently of one another if need be, occasionally talking or even arguing among themselves.
A vydrarch is 40 feet long from tail to head and weighs 10 tons.
Pathfinder Campaign Setting: Magnimar, City of Monuments, © 2012, Paizo Publishing, LLC; Authors: Adam Daigle and James Jacobs.