Immunity to water pressure damage- Adapt Body power (psion/wilder 5, psychic warrior 5), Expanded Psionics Handbook p.75/SRD
- Blackwater domain (granted power), Stormwrack p.109
- Construct Essence, Greater spell (sorcerer/wizard 9), Races of Eberron p.183
- Construct type, Monster Manual p.307/SRD
- Body of War spell (sorcerer/wizard 7), Spell Compendium p.35
- Emerald Perfection class feature (green star adept prestige class 10th level), Complete Arcane p.43
- Deep armor/shield property, Stormwrack p.128
- Deepdweller armor property, Magic Item Compendium p.10
- Etherealness special ability, Dungeon Master's Guide p.293/SRD
- Cloak of Etherealness magic item, Dungeon Master's Guide p.253/SRD
- Ethereal Form class feature (fiend of possession prestige class 1st level), Fiend Folio p.204
- Ethereal Jaunt spell (cleric 7, sorcerer/wizard 7), Player's Handbook p.227/SRD
- Ethereal Jaunt, Psionic power (nomad 7), Expanded Psionics Handbook p.105/SRD
- Etherealness spell (cleric 9, sorcerer/wizard 9), Player's Hanbook p.228/SRD
- Etherealness, Psionic power (psion/wilder 9), Expanded Psionics Handbook p.105/SRD
- Etherealness, Swift spell (beguiler 5, cleric 5, sorcerer/wizard 5), Player's Handbook p.113
- Helm of Underwater Action magic item, Dungeon Master's Guide p.259/SRD
- Incorporeal subtype/Incorporeality special ability, Monster Manual p.310/SRD/Dungeon Master's Guide p.294/SRD
- Eladrin Form spell (sorcerer/wizard 7), Book of Exalted Deeds p.97
- Ghostform spell (sorcerer/wizard 8), Spell Compendium p.103
- Permeable Form spell (sorcerer/wizard 3), Lords of Madness p.129
- Shed Body class feature (psion uncarnate prestige class 2nd level), Expanded Psionics Handbook p.149/SRD
- Uncarnate class feature (psion uncarnate prestige class 10th level), Expanded Psionics Handbook p.151/SRD
- Iron Body spell (earth 8, sorcerer/wizard 8), Player's Handbook p.245/SRD
- Iron Body, Psionic power (psion/wilder 8), Expanded Psionics Handbook p.113/SRD
- Oak Body power (psion/wilder 7, psychic warrior 5), Expanded Psionics Handbook p.122/SRD
- Necklace of Adaptation magic item, Dungeon Master's Guide p.263/SRD
- Planar Bubble spell (cleric 7, sorcerer/wizard 7), Spell Compendium p.158
- Pressure Capsules magic item, Dungeon Magazine 106 p.34
- Timeless Body power (psion/wilder 9), Expanded Psionics Handbook p.138/SRD
- Transformation of the Deeps spell (blackwater 4, druid 5, sorcerer/wizard 5), Stormwrack p.123
- Stone Body spell (cleric 6, sorcerer/wizard 6), Spell Compendium p.207
- Undead type, Monster Manual p.317/SRD
- Dry Lich class feature (walker in the waste prestige class 10th level), Sandstorm p.91; NOTE: Holy water damages undead creatures and evil outsiders almost as if it were acid. Which would then mean that, if totally immerged into water, a Dry Lich would take 10d6 per round, as per Acid Effects. You're immune to water pressure, but you also need to deal w/ this.
- Lich Transformation class feature (dread necromancer base class 20th level), Heroes of Horror p.87
- Lichdom class feature (death master base class 20th level), Dragon Compendium p.36
- Necropolitan template, Libris Mortis p.114
- Veil of Undeath spell (cleric 8, sorcerer/wizard 8), Spell Compendium p.229
- Water-Born power (egoist 3, psychic warrior 3), Stormwrack p.127
Creative use of
Minor Creation/
Major Creation/
True Creation/
Minor Creation, Psionic/
Major Creation, Psionic/
True Creation(, Psionic) and similar. Same execution (as in, the hamster ball) applies to
Telekinetic Sphere/
Resilient Sphere/
Telekinetic Sphere, Psionic and similar.
Anything which has
Regeneration + Immunity to
nonlethal damage, e.g.: Troll Blooded feat (Dr#319 p.61) + Improved Bonecraft Armor class feature (bone knight prestige class 4th level, Five Nations p.118).
Alter Self,
Polymorph,
Draconic Polymorph (Draconomicon p.79),
Polymorph Any Object,
Shapechange,
Metamorphosis, and
Metamorphosis, Greater can all be used to get this immunity through numerous ways, including the uses of Assume Supernatural Ability (SS p.30) or Metamorphic Transfer (EPH p.48/
SRD) to get "obscure" abilities (ex:
Ethereal Jaunt).
Limited Wish,
Miracle,
Wish,
Bend Reality,
Reality Revision, etc...
Honorable mention:
I May Be Tiny, But I'm IN-VIN-CIBLE!: The Gnome PowersuitStormwrack p.11:DEPTH
[spoiler]
Very deep water deals water pressure damage of 1d6 points
per minute for every 100 feet the character is below the
surface. A Fortitude save (DC 15, +1 for each previous
check) means that you take no damage in that minute.
Any creature with the aquatic type ignores pressure
for the first 500 feet of depth, and only takes 1d6 points
of damage per 200 feet below that when determining
vulnerability to pressure damage. For example, an aquatic
elf at a depth of 900 feet is subject to 2d6 points of pressure
damage per minute, as opposed to the 9d6 points of
pressure damage a surface dweller faces.
Some deep-dwelling creatures are completely immune
to pressure damage. Aberrations, elementals, and outsiders
with the aquatic subtype are generally immune to pressure
damage, as are certain other creatures adapted to the
environment (such as giant squids or whales).
[/spoiler]
There's the alternative of always succeeding on that Fort save, though you'll probably fail it somewhen even if you do not autofail on a 1, so it's not a viable option when you're 25/8 underwater. Are there any other things that gives <insert thread's name here>?