From Compendium of Worldly Lore
Astride the crashing waves comes the sea witch: a terrible chaotic mage who wields the power of water and calls on the living horrors of the deep. Mariners blame sea witches for every mysterious shipwreck or monstrous raid, even when such events occur naturally—and since sea witches thrive on destruction and fear, they do not protest.
Wizards and sorcerers with a love of violent weather magic are typical sea witches. However, it’s also possible for monstrous beings that already possess such innate abilities to enter the class: A naga, for example, could become a very powerful sea witch. A kraken with levels in an arcane spellcasting class could augment its already considerable abilities with the powers granted by this prestige class.
Role: Spell Utility
Characteristics: Conjurers of hellacious weather, nasty deepwater beasts, and curses
Source: Stormwrack
Game Rule Information
The Sea Witch has the following game statistics.
Abilities: The caster classic, Dexterity to avoid damage, Constitution to stay alive with a d4 hit die and concentration check, and casting stat to weel have augmented casted.
Alignment: Any Chaotic
Hit Die: d4
Starting Gold: N/A
Class Skills
The Sea Witch's class skills are Concentration (Con), Craft (any) (Int), Knowledge (arcana) (Int), Knowledge (nature) (Int), Knowledge (the planes) (Int), Listen (Wis), Profession (any) (Wis), Search (Int), Spellcraft (Int), Spot (Wis), Swim (Str).
Skill Points at 1st Level: (2 + Int modifier) × 4
Skill Points at Each Additional Level: 2 + Int modifier
Class Features
All of the following are class features of the Sea Witch.
Weapon and Armor Proficiency: A Sea Witch is proficient with whatever they were already proficient with prior to taking levels in this class.
Curse of the Sea Witch Sp: The ocean is a vengeful, mercurial entity, and you're capable of awakening its dark side. Your curse functions like bestow curse, except that the target can remove it automatically by spending an hour more than a mile from the nearest large body of water. Starting at 3rd level, you can use this class feature twice per day.
Spellcasting: At each level indicated in Table 1-1: Sea Witch Progression, you gain new spells per day and an increase in caster level (and spells known, if applicable) as if you had also gained a level in an arcane spellcasting class to which you belonged before adding the prestige class level. You do not, however, gain any other class feature a character of that class would have gained. If you had more than one arcane spellcasting class before becoming a sea witch, you must decide which class gains each level for the purpose of determining spells per day, caster level, and spells known.
Call Maelstrom Su: On attaining 2nd level, you gain the innate ability to create a terrible whirlpool called a maelstrom (see page 13 for complete details on this phenomenon). The whirlpool persists for 1 hour per class level and can appear anywhere within 1 mile of you. This whirlpool has no special exit: Creatures ejected from the vortex must make their way back to the surface or away from the currents. You can create a maelstrom once per day. At 6th level, you can produce a major maelstrom once per day. This has no special exit, but you can locate the vortex so that it empties into an underwater feature such as a cavern, if the feature is within the whirlpool's depth. At 9th level, you can produce a greater maelstrom once per day. This vortex opens directly into the Elemental Plane of Water. You do not control the destination on that plane.
Briny Deep Summoning Sp: Starting at 4th level, you can summon a dire shark, echinoloth, or elder tojanida to attack your enemies and follow your commands for 1 round per arcane caster level. This spell-like ability otherwise functions like the highest-level summon monster spell you can cast. Starting at 8th level, you can employ this class feature twice per day. You can summon a caller from the deeps, a scyllan , or 1d4+1 dire sharks, echinoloths , or elder tojanidas.
Curse of the Albatross Sp: Beginning at 5th level, you're able to extend your curse to cover an entire ship and its crew. The ship takes a —10 foot speed penalty, and its crew takes a —4 penalty on Profession (sailor) and Swim checks. The curse of the albatross otherwise functions like bestow curse and can be ended with break enchantment, limited wish, miracle, remove curse, or wish. Moving away from a large body of water isn't sufficient to end this curse, but it might make it come into play less often. Starting at 7th level, you can use this class feature twice per day.
Call Phantom Ship Sp: At 10th level, you can create a eerily glowing longship with phantom rowers that crosses the seas at your command. The phantom ship, which lasts 1 hour per arcane caster level, is functionally a longship, except that it has an oar speed of 30 feet. The rowers are phantoms, AC 15 (+4 natural armor, +1 Dex), with 7 hp +1 hp per caster level. They won't do anything other than silently row.