FREQUENCY: Very rare <Unique>
FREQUENCY: Very rare ([Dungeon Level X])
NO. APPEARING: 1
ARMOR CLASS: -5
MOVE: 6" // 18"
HIT DICE: 90 hit points
% IN LAIR: 75%
TREASURE TYPE: [H], [S], [U]
NO. OF ATTACKS: 1
DAMAGE/ATTACK: 2-24 <(water wave)>
SPECIAL ATTACKS: Drowning, spells
SPECIAL DEFENSES: Immune=paralysis, Immune=petrification
SPECIAL DEFENSES: See below
MAGIC RESISTANCE: 70%
INTELLIGENCE: Genius
ALIGNMENT: Neutral evil
SIZE: L (20' diameter)
PSIONIC ABILITY: 210
    Attack/Defense Modes: All / all
LEVEL/X.P. VALUE: X | 23,000

Olhydra appears only near water as a watery amorphous blob 20' in diameter.
She attacks as a 20 hit dice monster once per round with a water wave which inflicts 2-24 points of damage. <edit>

Drowning: She can also attack by enveloping and drowning victims;
up to five <5> human-sized <(size M)> creatures may be attacked and enveloped at one time, <cf. DMG.63, for other sizes>
and are powerless to do anything (fight, CAST spells) while enveloped.
All defenders are considered armour class <AC> 6 against this attack (with appropriate magical and dexterity modifiers).
Victims drown in 2-8 rounds and take 2-12 hit points of damage each round in any case.
The only way to save enveloped victims is to kill or drive away the Princess <caps> since she cannot move enveloped bodies.
<note: the Drowning ability could be revised with the Hold Breath rules, in the WSG>

As Princess <caps> of evil water creatures,
Olhydra may summon one <1> of the following groups once per day <1 per day>:
    1-3 water elementals,
    1-2 sea hags,
    2-5 water weirds
    or 20-200 sahuagin (salt water only).

She can also perform the following thrice per day : <3 per day><each?><CL=20?>
    produce a triple-strength <(x3)> [wall of fog],
    lower and
    [part water] (at 20th level),
    [transmute rock to mud], <druidic?>
    [ice storm]. <perhaps replace ice storm with another water spell, as Olhydra is not from the Para-Elemental Plane of Ice>

Fire attacks are at +2 hit probability against her and do an additional 1 point of damage per attack die.
Cold attacks cannot damage her,
but if over 20 points in value,
they act as a [slow] spell upon her (her magic resistance is ineffective in this case, nor does she get a saving throw).
Any normal fire within 10' of Olhydra is automatically extinguished.
She cannot be paralysed or turned to stone. <edit>

Olhydra lives in a great undersea castle on the Elemental Plane of Water.
There is great enmity between her and Imix.