Hydras overpowered?

[Kid Charlemagne]

And don't forget that Lernean Pyrohydras can only be killed by cutting off all their heads and searing them with fire damage...

...and since they're Lernean Pyrohydras, they are immune to fire.

 

[Schmoe]

Cyro and Pyro hydras are, indeed, very dangerous if the party is cornered and doesn't have adequate protection. If the party has protective magic or is not cornered, well, defeating the hydra should be academic. I think by 14th level resourceful characters will have ways to secure either protection or distance from the thing.

On a related note, I'm about to throw this up against my party of six 6th level characters. It's a 9-headed hydra variant I've lovingly termed "The Sewer Beast." I expect the party to run if they have any sense ...



"A mass of serpentine necks rises out of the water, each one topped by a fearsome head with jaws big enough to bite a man in two. The necks all converge to become a single, slug-like mass that extends to the rear. Each head is vaguely reptilian in appearance. The skin of the monster, where it is visible beneath the slime and the mold, is black and scaly. The creature’s teeth come to needle-like points, and thick saliva drips from the corner of each mouth. Its black eyes gleam with malevolence, and its breathing is a gurgling rasp that issues from each of its nine gaping mouths."

Sewer Beast (Huge Magical Beast, CR 10, Chaotic Evil)
HD: 9d10+45 (97 HP); Initiative: +1; Speed: 20’, Swim 20’; AC: 17 (-2 Size, +1 Dex, +8 Nat); Attacks: 9 bites, +9 melee; Damage: 1d10+5+wounding; Face/Reach: 10’x30’/10’; Special: Slimy Skin, Wounding, Disease, Scent; Fort +11, Ref +7, Will +3; Str-21, Dex-12, Con-20, Int-8, Wis-10, Cha-14; Skills: Listen +10, Spot +11, Escape Artist +9; Feats: Combat Reflexes

Slimy Skin – The Sewer Beast’s skin is slimy and crusted with the algae and mold from decades of dwelling in sewage. This grants the creature Fire and Acid resistance of 5 and also grants the creature a +8 circumstance modifier to Escape Artist checks.

Wounding – Any wound inflicted by the Sewer Beast continues to bleed for an additional 1 HP of damage each round until the wound is bound (DC 15 Heal check), the creature receives magical healing, or the creature dies. Bleeding from multiple wounds is cumulative.

Disease – Any creature wounded by the Sewer Beast must make a Fortitude check (DC 13) or be infected by Filth Fever.

 

[James McMurray]

...and since they're Lernean Pyrohydras, they are immune to fire.

But not acid, which works just as well...

 

[Sigma]

I threw the party against a hydra once in the RtToEE. It was in a room with a passage it couldn't fit through and no cover. Needless to say, the party just stood back and peppered it with ranged attacks until it died. The morale of the story: hydra's don't have a ranged attack and can't fly. Even the breath weapon has a range. That's their big achilles heel.

 

[Ridley's Cohort]

Hydras are your basic offense heavy monster. Bad Will save, no effective range attack, and unremarkable HPs give an appropriately powerful party many ways to deal with it.