TEXT: Demon Tainted Waters
  Roll d20
  (1) Ten thousand fishhooks along fishing line 
  strung up between several large stones, organized 
  like a maze. Small glimmer of treasure in the 
  middle of the maze acts as bait, but it is not 
  valuable (shiny rocks and sand). If mermen are 
  chasing the party or are encountered near here they
  will attempt to chase the party inside, they know 
  the inns and outs of this area.
  (2) Several tropical fish swim in this miniature 
  reef. One of them is a bright orange 'Proud Puffer'.
  If molested the fish will puff up which also 
  unleashes a horrible noise through the water which
  will attract an Aquatic Encounter. Fish is worth 3 
  GP if captured alive and 1 GP if dead.
  (3) Dolphin graveyard. Several dolphin bones are 
  here, most arranged into long rows and columns. 
  Fish bones are even left here as if offerings for the 
  dead. 50% chance nearby dolphin pod is here but 
  they will not attack unless the graves are disturbed.
  They will fight any sharks they see, including (8).
  (4) Merman camp. Appears to be made of several 
  stacked stones and kelp as a 'roof'. Kelp 'curtain' 
  keeps out curious fish. The inside is dark but 
  seemingly has little of value except for a net, two 
  bone tridents and a pet octopus. The octopus is 
  hidden in a corner and blends in with the color, so 
  only someone very perceptive will notice it.
  10% chance the Merman Party [2] is here.
  (5) Seahorse grotto. 1d8 seahorses will appear here
  and will fight any intruders, but will not pursue 
  outside of the area. Half of them are male and are 
  very pregnant; killing them will release a cloud of 
  tiny baby seahorses that will blind anyone within 
  the cloud. 
  At the bottom of the grotto is a dead Seahorse with
  a silver dagger lodged in its skull. It is inscribed 
  with the words Liberation from Ourselves.
  Seahorse (1HD, Kick d6, AC 10, +2 AC when 
  moving) they can kick twice if they don't move, 
  but prefer hit and run tactics.
  (6) It's a Merdragon! It looks like a regular dragon 
  except without wings, stupidly small flippers on 
  the ends of its limbs and a large padded tail. 
  Surprisingly fast and agile. The dragon is gone but
  every minute grants a 10% chance it will return. 
  Outside of its cave is what looks like a dead 
  demon of some kind, ripped apart and left to the 
  small feeder fish that swim nearby. Will give chase
  but not if the party hides in small areas such as (7) 
  or (19), or if it sees another group of humanoids.
  Within the Merdragon's cave is its hoard. It has 
  treasure that is mostly created by the merman 
  (such as natural gold smashed into the shape of 
  fish, rare shells used to make expensive dyes on 
  the surface and several megalodon teeth used to 
  make a necklace) with some dubloons and silver 
  candlesticks from trading vessels. Also within the 
  treasure pile is d100 pearls with at least one pearl 
  being a magical, softly glowing pink pearl that 
  grants +1 when casting Charm or similar.
  Merdragon (HD 6, AC 16, Bite deals 2d6, Tail d6 
  to all hit in a cone behind it) Breath weapon; fires 
  out a riptide of water that pushes anyone back save
  vs breath weapon to avoid getting slammed into 
  something. This wastes a turn of anyone pushed 
  away so they need to swim back to the fight or if it
  pushes them back into rocks and coral instead that 
  person takes d8 damage. On a roll of 8 the person 
  is also knocked unconscious.
  (7) Craggy sea cave. Several entrances are only 
  big enough for a small person like a child to enter, 
  some are large enough for a person and some are 
  larger. The cave has many cracks and cervices 
  where one can look out if hiding from something 
  (like a Merdragon). The cave also contains d6 
  tainted crabs. These crabs appear small and 
  harmless but are overly aggressive. If killed or if 
  around the party too long the crabs will start to 
  foam up and release weird fluid into the water that 
  will make that person tainted. This means all 
  demon's will treat that person as friendly but that 
  person will ping as evil or of abyssal origin.
  If the party sleeps, camps, or spends a few hours 
  inside the cave roll on encounters to find out what 
  is lurking just outside when they leave it.
  
  (8) The blind shark. What appears to be an evil 
  looking tiger shark is actually surprisingly 
  friendly. The poor thing is starved because it can't 
  hunt very well without sight; its not actually blind 
  it just has poor eyesight. If fed the shark will 
  become friendly to the party and will even follow 
  them around to the best of its ability. Has 1d6+2 
  HP and a d6 bite attack, can only attack in good 
  light conditions or if is trained to attack an enemy.
  (9) Strange coral. This area is reef-like and has one
  kind of weird coral in it; roll a d6.
  1. Bright red coral. If it touches bare skin or 
  is used as an attack save vs poison or take 
  1d4 damage. This coral creates a horrible, 
  shooting pain and if the victim is holding 
  their breath they will be unable to hold it 
  when struck by this coral. Mermen may 
  use this for weapons; Coral Spear, etc.
  2. Green membrane coral. Looks like a brain; 
  if touched with bare skin it instantly deals 
  1 damage to the character's Int. Magic 
  users must save vs magic or lose 1 spell of 
  the lowest level memorized for today.
  3. Yellow Tree-like coral. Does not seem to 
  have any special properties, but it loses 
  color if introduced to an area with 
  poisonous water. Most merman carry a 
  small twig up to a full branch.
  4. Brown shelf coral. Dull colored coral that 
  grows out in mostly straight shelves. 
  Mermen use them for furniture and plates.
  5. Demon spore coral. This coral looks like 
  small spikes and is growing over the other 
  types. The infection grows very fast.
  6. Roll again but with a Merman gatherer 
  who is tending to the coral, gathering it, or 
  fighting it if its demon spore.
  (10) What appears to be a knight in full plate 
  armor. Is skeletal and the armor is rusted beyond 
  any usefulness. Inside the armor lives 2d4 
  carnivorous fish that pop out and deal 1 damage 
  per fish each round, swarming around whoever 
  disturbed the armor. Can only be chased away 
  after many rounds of flailing, each has only 1 HP.
  The Knight appears to also have a golden tooth 
  and handkerchief. It is actually a dead pirate, 
  thrown overboard wearing a knight's armor.
  (11) Regular patch of ocean but with some weird 
  phenomena as a result of the demonic taint. 1d8
  1. Low Oxygen water. If party members are 
  aquatic and breath it or have the means to 
  breath water this water will still make them
  weak and maybe knock them out. This 
  appear is very dead and a few fish can even
  be seen floating belly up.
  2. Extremely murky water. Can't see hand in 
  front of face, very easy to get lost. 25% 
  chance home to an opportunistic shark.
  3. Evil laughter can be heard here. If anyone 
  in the party is evil, tainted, or part demon 
  in ancestry they don't hear anything.
  4. Fish found in a totally different biome. If 
  near the surface you will find abyssal fish, 
  if deep in the water you will find surface 
  fish instead.
  5. Fire burning in the center of a small ring of
  stones. Gives off light and warmth just like
  a real fire. If one of the stones is moved it 
  stops and doesn't come back.
  6. Large bubble of air stuck to the ground. 
  Going into it is like passing through a 
  waterfall, the inside is filled with perfectly 
  breathable air and even has grass and 
  flowers. Nothing of value is here though.
  7. Upside down whirlpool. If entered you get 
  shot out into the sky and then fall back into
  the ocean nearby. Playful seals and 
  dolphins are using it to have fun.
  8. Roll twice and take both.
  (12) Group of 1d4+1 Mermen burying a blob-like 
  demonic jellyfish that slithers across the ground 
  underneath piles of stones. If they are interrupted 
  the demon will be released and will scoot off 
  towards (2), (5), and (18) to feast. One of the 
  Mermen has a tentacle staff.
  (13) Generic shipwreck of a small viking-like 
  vessel. Within is a magic shield that can be thrown
  and return like a boomerang but it doesn't work 
  underwater. If the party is not at least 50% 
  Fighters or they disturb the remains 1d4+1 
  skeleton vikings will rise up and try to kill the 
  intruders with whatever they can find.
  
  (14) Merman base. Small colony of Mermen, at 
  least 3d6+3 of them; at least one of them is a 
  shaman that knows 1st and 2nd level cleric spells. 
  Not all of them are here at one time; they go to and
  fro during the day. Most return at night to sleep, 
  but they keep guards posted. They have two pet 
  octopi within their compound that will attack 
  intruders; they like to crawl and nap over 
  doorframes. There are also several traps nearby, 
  such as clams that trap a person's foot inside of 
  them and the dangerous red and green coral.
  Any merman scouting parties will take anyone 
  suspected of being demons back here and capture 
  them. They will also force them to touch Brain 
  Coral directly; their shaman knows how to extract 
  some of the 'mind' found within. 1d4 green tablets 
  are in his workshop, swallowing one grants a 
  random memory. (roll on the Memory table.) None
  of these Mermen will speak common but do not 
  attack directly; they do however point their 
  weapons at intruders and try to get them to leave. 
  There is a 50% chance their special character party
  is present (see Mermen party table).
  Within their storage room is several gold coins, 
  some rare alchemical reagents, 1d4 more green 
  tablets, multiple nets and tridents, and a month's 
  worth of bottled and jarred fish and fish-eggs.
  (15) Demon murders. Several fish were tortured 
  here, staked onto poles and eaten by other smaller 
  fish. One merman corpse is also here, eyes 
  removed. This place radiates evil and will lead 
  anyone that uses Detect Evil to it. 25% chance a 
  Merdemon will be here, doing grisly things.
  Merdemon (2HD, 12 AC, 1d4 stingray tail and 1d6
  spear. Has +1 to hit, damage, and AC while within 
  this area, strengthened by the evil aura).
  If anyone in the party is evil, tainted, or was once 
  an executioner or torturer he will be amicable and 
  even talkative, but offended if they refuse to eat 
  any Merman meat he has prepared for guests. 
  Wishes to torture and kill things here to summon 
  more demons, but having trouble drawing runes in 
  water. If turned he squirts ink like an octopus.
  (16) Merimp swimming around in a turtle shell, 
  pretending to be a turtle. (stats as goblin, but 
  aquatic). The imp is also an evil little demon but is
  cowardly and will do anything anyone says if 
  forced out of his shell. Currently looking for things
  to steal and put inside his hoard; which is nothing 
  more then a small crack in the rocks. (2d6 silver)
  The Merimp is mostly harmless and useless but 
  has some information on the demonic taint 
  developing in this area. He claims that a Sorcerer 
  wished to become king of the sea but the position 
  was already taken by the king of the Mermen, so 
  he waged war on the Merpeople. He eventually 
  lost and was killed, but not before unleashing a 
  curse that infected the area with infernal energies. 
  50% chance for this story to be complete and utter 
  bullshit, the Imp also wishes payment for info.
  (17) Sunken, unopened treasure chest. 50% chance
  the party gets here first and then the Merman party
  appears, otherwise the Merman party gets here 
  first. They would be unwilling to share and will 
  attack the party if they seem overly tainted; but a 
  skilled negotiator may be able to share the loot.
  Within the chest is... (roll d10)
  1. Mummified cat, now soaking wet. It has a 
  small gemstone embedded in its paw.
  2. Demonic Urchins. They release a cloud of 
  tainted water tainted everyone nearby.
  3. Tiny Gold Crown. If inspected it appears as
  a toy crown for children, but is still made 
  of actual real gold. No gemstones.
  4. Small shining silver chain. Wearing it gives
  +1 vs save or die effects.
  5. Five gemstones; random type and quality.
  6. Set of Silverwear. The dinner spoons are 
  inscribed with one very common name 
  each (Jack, Jill, etc), as if belonging to that 
  family member.
  7. Delicate and handcrafted Wizard's wand 
  locked in an airtight, waterproof container.
  8. Smoking herb that brings Euphoria. If must
  be dried out for days now to use it.
  9. Several religious items used in the worship 
  of sea-spirits. Using them grants a +1 to 
  luck and swimming, but only if untainted.
  10. Spellbook. Sadly ruined by water.
  
  (18) Dead whale, stuck up on a sandbar. It's body 
  is currently being ravaged by a huge number of 
  tiny fish, crabs, and microorganisms. The party 
  could potentially get something useful here, if not 
  from the whale itself then from the life around it.
  25% chance that a Merimp is here guiding a large 
  number of demonic hagfish and trying to get them 
  to spawn and reproduce.
  If the party spends more then 10 minutes in this 
  location, roll on the Encounters table.
  (19) Kelp forest. Useful for cover and hiding from 
  any nearby encounters or dangerous foes, such as a
  Merdragon. Within this forest is a group of 2d4 
  ferocious Sea Otters. (stats as wolf, but +2 AC). 
  Every hour another 1d4 will return to this location.
  The otters won't chase if the party leaves, unless if 
  the party has been tainted. The otters will also not 
  return to the kelp forest if the party has (8) or if 
  they are hiding from a shark.
  Hidden within the kelp forest is a magic starfish 
  that grants a one time regeneration effect to a 
  person. It has almost been hunting to extinction.
  (20) Witch Boat. Small vessel overhead that 
  appears to have a hole in the bottom. The hole is 
  actually a moon pool, safely allowing access to the
  water below without sinking the ship. If 
  approached or entered the party will probably 
  encounter a friendly witch. She is willing to trade 
  ocean maps of this area as well as general goods 
  for any samples of demon tainted animals or 
  plants. If the party is tainted she will offer to cure 
  it for 3 Silver each, claiming it is the only way to 
  remove the taint. (This is a lie. The taint will wear 
  off in about a week or less if the party goes on 
  land or bathes regularly.)
  The Sea Witch is armed with a tentacle staff, 
  several spells, and guards who wear diving suits 
  seemingly made out of kelp and fishbone.
  Wandering Encounters Table
  Roll d6
  [1] Demon Hagfish (HP 1 each, 1 damage bite 
  each, AC 14, slippery and hard to handle)
  The hagfish travel around in a cluster and mostly 
  only eat dead things. Will attack untainted people.
  [2] Mermen Party. This is the group the Mermen 
  are using to scout the nearby area and bring back 
  demon-tainted things and people to kill or capture 
  them; they will also be called to defend the 
  Merman compound if attacked by the players.
  Scaler the Thief. Speaks common, carries a coral 
  dagger. Has the modified Thief skill Swim Silently 
  at 50% or 3 in 6.
  Bondero the Fighter. Uses several bone weapons 
  and carries a net. Has a bag of poisonous urchins 
  (1d6 poison damage, save for half) that he uses as 
  traps or flung at enemies.
  Fishface the Fighter, +1 HD. Bone harpoon, shell 
  armor grants +2 AC. She has a fish-like face as 
  well as a mermaid's tail, making her rather ugly. 
  Claims she was cursed by a jealous goddess, but 
  could have also been born like that.
  Umar the Cleric. Old and slow, mostly stands back
  and casts healing spells or bless. Surprisingly 
  speaks Dwarven, learned from stone tablets that 
  fell in the ocean. Worships a Dwarvish God.
  Innmar Brightfin (Magic User). Comes from the 
  Merman aristocracy, not a local. Knows the Water 
  Orb spell, uses this to help capture people. Not 
  afraid to get in close with his bone knife.
  [3] Huge Jellyfish (HD 3, 11 AC, very slow and 
  can't chase or escape. 4 stingers that deal d4 
  damage and have save or get stunned for a round). 
  Going along its merry way, peacefully. 50% 
  chance for it to be tainted, meaning it wishes to 
  inflict pain and suffering. Intentionally keeps 
  victims alive as long as possible but stunned 
  constantly and hurt by its horrible stingers. Tainted
  version does not attack tainted people.
  [4] Reef Shark (HD 2, 12 AC, Bite d8) On the first 
  round of combat the shark will charge giving +2 to
  Hit and damage. Won't usually attack party unless 
  they are already injured (blood in the water) or 
  smell like food. 50% chance for tainted version, 
  which will attack no matter what and fights to the 
  death; doesn't attack tainted people.
  [5] Two Mermen scouts (As bandit, but aquatic) 
  Only 25% chance to encounter them normally; 
  they will follow the party instead and report back 
  to the compound if the party is not attacked by 
  demons; then Mermen will know party is tainted.
  
  [6] Sea Turtle (1HD, 18 AC, d4 bite, cowardly)
  The Sea Turtle does not fight unless tainted. 
  Tainted turtle isn't very useful but likes to spray 
  taint around itself when it fights, tainting whoever 
  gets too close. Once it taints the whole party it will
  just leave.
  Magic Item- Tentacle Staff
  Appears as a metal rod with rubbery lumps on the 
  end. This magic item can create up to 3 tentacles at
  a time from the end of it. Each tentacle can either 
  whip at enemies in front of the user (dealing 1 
  damage each tentacle, ignoring AC, knocking 
  them back or keeping them away) or can attempt 
  to constrict (make an attack roll +1). If constricted,
  the Tentacles can squeeze for d4 damage EACH. 
  The tentacles can also pick up objects, open doors,
  carry things, anything a tentacle could do.
  The tentacle staff is unique in that using a tentacle 
  does not permanently expend it; instead it can be 
  drawn back into the staff and saved again for later 
  use. If any tentacle takes 1 point of damage 
  however it will fall off the staff, expending that 
  tentacle.
  When found, each tentacle staff has 2d4 Tentacles 
  remaining inside it, ready to be used.
  Random Memory Table
  Whenever you eat a Green Tablet; Roll d10
  [1] Suicidal memory of jumping into the ocean 
  with a heavy weight tied around foot. Sad, but 
  otherwise useless.
  [2] Memory of a scholar examining Atlantean 
  Languages and artifacts. You might be able to stop 
  the Mermen from attacking by shouting some of 
  these words; 1 in 6 chance.
  [3] Memory of a Merman seeing and hiding from a
  Sea Dragon. Gives a general direction to (6), (7), 
  and (19).
  [4] You have memories of savage hunting and 
  dominance in the ocean. You remember being a 
  shark; otters are now innately scared of you.
  [5] You have the memories of a Merman alchemist
  or medicine man. You know the inherit uses of 
  each type of coral and also you know about the 
  existence of the magic starfish at (19).
  [6] You remember playing gleefully with the 
  dolphins in the reef. The dolphins at (3) will be 
  friendlier and one will even follow you around as a
  companion and help fight until it reaches half 
  health, the party camps, or the party leaves the 
  water. (Dolphin 1HD+1, 11 AC, Ram attack d4, 
  high speed. Can spot enemies and signal them to 
  party with high pitched calls.)
  [7] Short and violent memory of you nearly dying. 
  You are kicked to hell by a bunch of seahorses but 
  not before jamming your lucky silver dagger into 
  one of their skulls and escaping. You know of the 
  dagger at (5) and have some vague clues about this
  character; you even have a hunch they headed 
  south from here for later adventuring.
  [8] Merman trapper. You know the path of (1) and 
  you know where the hidden traps are at (14).
  [9] You have the entire sad tale of the Merman's 
  lover memorized now in your mind. It details a 
  young woman who loved a Merman and wished to
  be with him so much she slaved away to buy a 
  potion that would let her breath water. When she 
  finally bought it she jumped into the sea, but in her
  excitement she speared herself against the rocks 
  below. The morale is look before you leap and 
  love makes you stupid. This tale is short and sad 
  but will probably make a wench or two heart's 
  swoon after you. Otherwise, nothing useful.
  [10] You have the memories of being the lucky 
  fish. Lucky fish are not found in this area but one 
  of them apparently wandered here, at least long 
  enough to touch a green coral and deposit this 
  magical memory, which only functions once. 
  The next time you get a critical failure or fumble, 
  treat it instead as a critical success.
  
SOURCE: textdata/thevault/_GM Books/World Building & Game Design/Game Mastering and Design/Tables/Demon Tainted Waters.pdf