Glaistig (CR 6)

Medium Fey
Alignment: Always chaotic neutral
Initiative: +1 (Dex); Senses: low-light vision, Listen +9, and Spot +8
Languages: Common, Elven, and Sylvan

AC: 15 (+1 Dex, +4 natural), touch 11, flat-footed 14
Hit Dice: 6d6+12 (33 hp); DR: 5/cold iron
Fort +4, Ref +6, Will +9
Speed: 30 ft., swim 50 ft.
Space: 5 ft./5 ft.
Base Attack +3; Grapple +4
Attack: Bite +4 melee or dagger +4 melee
Full Attack: Bite +4 melee and dagger +4 melee
Damage: Bite 1d6+1, dagger 1d4+1/19-20
Special Attacks/Actions: Beguiling song, blood drain, spell-like abilities
Abilities: Str 12, Dex 13, Con 14, Int 13, Wis 14, Cha 19
Special Qualities: resistance to cold 10 and fire 10, water breathing, water symbiosis
Feats: Ability Focus (beguiling song); Alertness; Iron Will
Skills: Bluff +14, Diplomacy +12, Disguise +12 (+14 acting), Escape Artist +7, Hide +3, Intimidate +12, Knowledge (nature) +5, Listen +9, Move Silently +7, Sense Motive +11, Spot +8, Swim +18, and Use Rope +1 (+3 with bindings)
Advancement: By character class
Climate/Terrain: Temperate forests
Organization: Solitary
Treasure/Possessions: Standard

Source: Monster Manual III

Beguiling Song (Su): A glaistig can attempt to beguile creatures with its song. A glaistig sings, targeting a single creature it can see within 300 yards of the body of water to which it is linked (see Water Symbiosis, below). This is a sonic charm effect, and the creature must be able to hear the glaistig for it to take effect. The targeted creature must make a DC 19 Will saving throw. A creature that successfully saves cannot be affected again by the same glaistigs song for 24 hours.

Failure indicates the creature is beguiled and moves toward the glaistig, taking the most direct route available. If that path leads into a dangerous area (such as very deep or fast-moving water), the beguiled creature gets a second saving throw. If that save is successful, the beguiling effect is broken, and that creature cannot be affected by that glaistig's song for 24 hours.

A glaistig that desires a companion often moves out of the water and bestows water breathing upon its beguiled victim so it can take him underwater. A beguiled creature takes no actions other than to defend himself. (Thus, a fighter cannot run away or attack, but takes no defensive penalties.) A beguiled victim that moves within 5 feet of the glaistig must make a DC 19 Will saving throw or be charmed, as by the charm monster spell cast by an 8th-level sorcerer. A creature that successfully saves cannot be affected again by the same glaistig's song for 24 hours. The beguiling effect continues so long as the glaistig sings. A glaistig does not need to continue singing to keep a victim charmed.

A glaistig can use its beguiling song both above and below the water. Most glaistigs move into deep water, forcing a beguiled victim to move toward them. If these unlucky creatures fail their second saving throw, they usually drown (see Drowning). The save DC is Charisma-based.

Blood Drain (Ex): A glaistig can suck blood from a living victim with its fangs by making a successful grapple check. If it pins the foe, it drains blood, dealing 1d4 points of Constitution drain each round the pin is maintained.

Spell-like Abilities: At will - dancing lights, fog cloud, hypnotism (DC 15), suggestion (DC 17); 1/day - water breathing. Caster level 8th.

Water Breathing (Ex): A glaistig can breath either water or air.

Water Symbiosis (Su): Each glaistig is mystically bound to a body of water or a waterway as small as a pond or as large as a lake or river. A glaistig cannot move more than 300 yards away from its body of water and still breathe normally. If a glaistig strays farther away, it must hold its breath or immediately start to suffocate (see Suffocation). Once a glaistig has moved beyond the boundary of its connection, it cannot breathe normally until it has immersed itself in its body of water.

Skills: Glaistigs have a +4 racial bonus on Bluff and Sense Motive checks. A glaistig has a +8 racial bonus on any Swim check to perform some special action or avoid a hazard. It can always choose to take 10 on a Swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.

A glaistig uses its beguiling song to lure victims close to the water, targeting specific individuals. If a large group comes close to its lair, it will lurk beneath the surface until only one or two targets remain. A glaistig is mystically bound to its watery lair and cannot move more than 300 yards away from it.

Once a victim is within striking distance, a glaistig will cease singing and grapple the opponent. If the grab is successful, it will drain blood for as long as possible. If reinforcements arrive, the glaistig will try to use suggestion, hypnotism, or fog cloud to cause a diversion and slip beneath the surface of its watery home.