Octopus, Blue-Ringed (Hapalochlaena)
Diminutive Animal (Aquatic)
Hit Dice: ½d8–1 (1 hp)
Initiative: +2
Speed: 10 ft. (2 squares), swim 30 ft.
Armor Class: 16 (+4 size, +2 Dex), touch 16, flat-footed 14
Base Attack/Grapple: +0/–2*
Attack: Arms +6 melee (0)
Full Attack: Arms +6 melee (0) and bite +1 melee (poison)
Space/Reach: 1 ft./0 ft.
Special Attacks: Gnawing beak [grapple or +6 melee, poison], improved grab, poison
Special Qualities: Chameleon, ink cloud, jet, low-light vision, rubbery body
Saves: Fort +1, Ref +4, Will +1
Abilities: Str 1, Dex 15, Con 9, Int 2, Wis 12, Cha 3
Skills: Climb +8, Escape Artist +12, Hide +18, Listen +3, Move Silently +4, Spot +5, Swim +10
Feats: Alertness, Weapon Finesseᴮ
Environment: Warm aquatic
Organization: Solitary
Challenge Rating: 2
Advancement: —
Level Adjustment: —
A miniscule octopus, its body is the size of a large walnut and the spread of its tentacles would barely be wider than your hand. It changes colour to a creamy white and yellow and bright blue rings rimmed in black start flashing upon its skin.
Blue-ringed octopuses inhabit shallow tropical reefs. Timid and unaggressive, they happen to be one of the most venomous animals in the ocean. These cephalopods eat fine-sized animals, mostly crustaceans such as shrimp. A blue-ringed octopus can live up to 2 years or so. Apart from their lethal poison their habits and lifecycle are pretty typical for an octopus their size.
A blue-ringed octopus weighs between one and three ounces and range from 6 to 8 inches in arm-span.
Combat
A blue-ringed octopus only attacks to catch food or defend itself. Should it feels threatened, the octopus normally tries to hide or flee. If that prove ineffective it flashes a blue-ringed warning display as described above. The octopus only uses its venomous bite as a last resort in response to an actual attack or persistent provocation (such as someone being foolish enough to pick it up or prod it repeatedly). Blue-ringed octopuses are so mild-natured they may tolerate some handling, but doing so is highly inadvisable!
Chameleon (Ex): A blue-ringed octopus can change its colour, combined with a limited ability to alter its body-shape and texture this gives it a +4 racial bonus on Hide checks. The octopus does not need cover or concealment to attempt a Hide check if it can match the colour of its surroundings.
s
Gnawing Beak (Ex): A blue-ringed octopus can bite an opponent it is grappling as a primary attack (bite +6 melee for poison damage) or by succeeding at an opposed grapple check (for the same damage). If the blue-ringed octopus spends a full-round attack to make the opposed grapple check, its gnawing beak damage ignores damage reduction and hardness of up to 6.
Improved Grab (Ex): To use this ability, a blue-ringed octopus must hit an opponent of any size with its arms attack. It can then attempt to start a grapple as a free action without provoking an attack of opportunity. If it wins the grapple check, it establishes a hold and can use Gnawing Beak.
*A blue-ringed octopus has a +15 racial bonus on grapple checks.
Ink Cloud (Ex): A blue-ringed octopus can emit a cloud of jet-black ink 1 feet high by 1 feet wide by 1 feet long once per minute as a free action. The cloud provides total concealment, which the octopus normally uses to escape a losing fight. All vision within the cloud is obscured.
Jet (Ex): An octopus can jet backward once per round as a full-round action, at a speed of 200 feet. It must move in a straight line, but does not provoke attacks of opportunity while jetting.
Poison (Ex): The bite of a blue-ringed octopus is painless but injects blue-ringed octopus venom, a lethal neurotoxin created by symbiotic bacteria in its saliva glands. This toxin permeates every organ in the octopus’s body, so anything foolish enough to eat the octopus's flesh will be exposed to blue-ringed octopus organ poison (merely biting the octopus will not result in poisoning if the attacker does not swallow its flesh). Fortunately, blue-ringed octopus poison is a lot less potent when ingested.
Blue-Ringed Octopus Venom: Injury, Fortitude DC 17, initial damage 1d3 hours of suffocating paralysis plus 1 point of Dexterity damage, secondary damage increases suffocating paralysis to 2d4 hours and adds 1d2 points of Dexterity damage. The save DC is Constitution-based and includes a +8 racial adjustment.
Blue-Ringed Octopus Organ Poison: Ingestion, Fortitude DC 15, initial damage 1 hour of suffocating paralysis, secondary damage increases suffocating paralysis to 1d4 hours and adds 1d2 points of Dexterity damage. The save DC is Constitution-based and includes a +6 racial adjustment.
The truly dangerous aspect of blue-ringed octopus poison is its suffocating paralysis effect. A creature who fails a Fortitude save against the poison start to feel the symptoms 15 minutes later. They become numb, lethargic and uncoordinated and may also tremble and/or suffer diarrhoea. The victim moves at half their normal speed, can neither run nor charge and suffers a –4 penalty to attack rolls, ability checks and skill checks plus a –2 penalty to Reflex saves and damage rolls. In addition, the victim must succeed at a DC 10 Fortitude save or begin to suffer paralysis and suffocation (see next paragraph). The save must be repeated every 15 minutes, with the DC increasing by +1 for each previous success, up to a maximum equal to the poison’s DC of 17.
The paralysis follows the normal rules: the victim remains fully conscious but cannot move or act (They may experience seizure-like fits and nauseated vomiting, but are unable to move their body voluntarily). The suffocation is caused by the poison paralyzing the victim’s diaphragm and chest so they cannot draw breath into their lungs. A suffocating victim takes 1d6 points of nonlethal damage every 15 minutes. If the victim falls unconscious from this nonlethal damage, they drops to –1 hit points and are dying, they then take 1 point of normal damage per round until they suffocate to death. If no magical means of delaying or neutralizing the poison is available, the victim’s life can still be saved through artificial respiration, if another character succeeds at a DC 17 Heal check during a 15 minute suffocation period they prevent the victim taking any suffocation damage during that period. This requires continuous attention from the healer, who cannot leave the victim for more than a few rounds without rendering that period’s treatment worthless. The effects of the poison (incoordination, paralysis & suffocation) continue until the suffocating paralysis duration expires or the victim does.
A creature who is immune or resistant to paralysis (such as a true dragon) applies this immunity or resistance to the poison’s suffocating paralysis effect and only takes Dexterity damage.
Rubbery Body (Ex): The only hard part of an octopus is its beak, the rest of its body is soft flesh the animal can contort through muscular action. This allows an octopus to squeeze through tiny gaps, passing through such openings as if it were a creature one size smaller than its actual size. A blue-ringed octopus's bonelessness grants it a +10 racial bonus on Escape Artist checks.
Skills: A blue-ringed octopus's chameleon ability gives it a +4 racial bonus on Hide checks and its rubbery body gives it a +10 racial bonus on Escape Artist checks.
An octopus has a +6 racial bonus on Climb checks and 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. An octopus can use either its Dexterity modifier or Strength modifier on Climb checks and Swim checks, whichever is better.
Poison-Ink Blue-Ringed Octopuses
The ink of Hapalochlaena is known to contain the same poison as its organs and saliva, so it's possible the animal might be a Poison-Ink Cephalopod as described in the Ink Variants section of the separate Squid Redux entry. This would change the octopus's abilities as follows:
Ink Cloud (Ex): A poison-ink blue-ringed octopus can emit a cloud of poisonous jet-black ink 1 feet high by 1 feet wide by 1 feet long once per minute as a free action. The cloud provides total concealment, which the octopus normally uses to escape a losing fight. Any water-breathing creature that breathes in the ink cloud is exposed to the octopus's poison. All vision within the cloud is obscured.
Poison (Ex): The bite of a poison-ink blue-ringed octopus is painless but injects blue-ringed octopus venom, a lethal neurotoxin created by symbiotic bacteria in its saliva glands. This toxin permeates every organ in the octopus’s body, so anything foolish enough to eat the octopus's flesh will be exposed to blue-ringed octopus organ poison (merely biting the octopus will not result in poisoning if the attacker does not swallow its flesh). The affected organs include the octopus's ink sac, any water-breather that enters a blue-ringed octopus's ink cloud is affected by blue-ringed octopus ink toxin. Fortunately, blue-ringed octopus poison is a lot less potent when inhaled or ingested.
Blue-Ringed Octopus Ink Toxin: Inhaled, Fortitude DC 13, initial damage 1d10 minutes of momentary paralysis, secondary damage increases momentary paralysis duration to 1d6×10 minutes and adds 1 point of Dexterity damage. The save DC includes a +4 racial adjustment.
Blue-Ringed Octopus Venom: Injury, Fortitude DC 17, initial damage 1d3 hours of suffocating paralysis plus 1 point of Dexterity damage, secondary damage increases suffocating paralysis to 2d4 hours and adds 1d2 points of Dexterity damage. The save DC is Constitution-based and includes a +8 racial adjustment.
Blue-Ringed Octopus Organ Poison: Ingestion, Fortitude DC 15, initial damage 1 hour of suffocating paralysis, secondary damage increases suffocating paralysis to 1d4 hours and adds 1d2 points of Dexterity damage. The save DC is Constitution-based and includes a +6 racial adjustment.
Momentary paralysis takes effect almost immediately; one round after failing their Fortitude save the victim suffers a –1 penalty to attack rolls, ability checks and skill checks; if the duration of the poison is measured in minutes then one minute after being poisoned the symptoms worsen, the victim can neither run nor charge and suffers a –2 penalty to attack rolls, ability checks and skill checks plus a –1 penalty to Reflex saves and damage rolls. The poison's penalties continue until the momentary paralysis duration ends. A creature who is immune or resistant to paralysis (such as a true dragon) applies this immunity or resistance to the poison’s momentary paralysis effect and only takes Dexterity damage. Penalties from ink poison's momentary paralysis do not stack with penalties from other forms of paralysis, such as those imposed by the suffocating paralysis of a blue-ringed octopus's venom and organ poison.
The truly dangerous aspect of blue-ringed octopus poison is its suffocating paralysis effect. A creature who fails a Fortitude save against the venom or organ poison at first feels identical effects to the ink toxin's momentary paralysis, but the symptoms become far worse after 15 minutes. The victim become numb, lethargic and uncoordinated and may also tremble and/or suffer diarrhoea. The victim moves at half their normal speed, can neither run nor charge and suffers a –4 penalty to attack rolls, ability checks and skill checks plus a –2 penalty to Reflex saves and damage rolls. In addition, the victim must succeed at a DC 10 Fortitude save or begin to suffer total paralysis and suffocation (see next paragraph). The save must be repeated every 15 minutes, with the DC increasing by +1 for each previous success, up to a maximum equal to the poison’s DC of 17.
The total paralysis follows the normal rules: the victim remains fully conscious but cannot move or act (They may experience seizure-like fits and nauseated vomiting, but are unable to move their body voluntarily). The suffocation is caused by the poison paralyzing the victim’s diaphragm and chest so they cannot draw breath into their lungs. A suffocating victim takes 1d6 points of nonlethal damage every 15 minutes. If the victim falls unconscious from this nonlethal damage, they drops to –1 hit points and are dying, they then take 1 point of normal damage per round until they suffocate to death. If no magical means of delaying or neutralizing the poison is available, the victim’s life can still be saved through artificial respiration, if another character succeeds at a DC 17 Heal check during a 15 minute suffocation period they prevent the victim taking any suffocation damage during that period. This requires continuous attention from the healer, who cannot leave the victim for more than a few rounds without rendering that period’s treatment worthless. The effects of the poison (incoordination, paralysis & suffocation) continue until the suffocating paralysis duration expires or the victim does.
A creature who is immune or resistant to paralysis (such as a true dragon) applies this immunity or resistance to the poison’s suffocating paralysis effect and only takes Dexterity damage.
Giant Blue-Ringed Octopus
Small Animal (Aquatic)
Hit Dice: 2d8 (9 hp)
Initiative: +3
Speed: 10 ft. (2 squares), swim 30 ft.
Armor Class: 15 (+1 size, +3 Dex, +1 natural), touch 14, flat-footed 12
Base Attack/Grapple: +1/+8*
Attack: Arms +5 melee (0)
Full Attack: Arms +5 melee (0) and bite +0 melee (1d3 plus poison)
Space/Reach: 5 ft./5 ft.
Special Attacks: Gnawing beak [grapple or +5 melee, 1d3+1 plus poison], improved grab, poison
Special Qualities: Chameleon, ink cloud, jet, low-light vision, rubbery body
Saves: Fort +3, Ref +6, Will +1
Abilities: Str 12, Dex 17, Con 11, Int 2, Wis 12, Cha 3
Skills: Climb +9, Escape Artist +13, Hide +15, Listen +3, Move Silently +6, Spot +5, Swim +11
Feats: Alertness, Weapon Finesseᴮ
Environment: Warm aquatic
Organization: Solitary
Challenge Rating: 3
Advancement: 3 HD (Small)
Level Adjustment: —
An octopus of impressive size, its body is the size of a football and its eight tentacles are about as long as a human is tall. It changes colour to a creamy white and yellow and bright blue rings rimmed in black start flashing upon its skin.
A giant version of the blue-ringed octopus. It too is a highly venomous octopus that inhabits tropical reefs, although it prefers the canyons and edges of over the shallow reef-tops favoured by normal blue-rings, since these have plenty of space to accommodate their larger bodies. The poison of a giant blue-ringed octopus is much less concentrated than its smaller cousin’s, but the greater volume of neurotoxin in its saliva glands and organs means it’s at least as lethal.
Unlike their timid diminutive relatives, giant blue-ringed octopuses are bold and inquisitive. They are so confident that other creatures will respect the lethality of their venom they tend to react to intruders with curiosity rather than fear. Their habits and intelligence are similar to other octopuses and they have lifespans of 3 to 5 years.
This octopus typically weighs around 30 pounds and has an arm span from 10 to 15 feet across.
Combat
A giant blue-ringed octopus only willingly attacks to catch food or defend itself. If it feels threatened it usually flashes a blue-ringed warning display as described above, but if the opponent is obviously dangerous the octopus normally attempts to flee or hide before trying to warn them off. A giant blue-ringed octopus only fights if cornered or attacked. In combat the animal tries to grapple opponents in its arms and then bite them with its venom-injecting beak, employing its improved grab then gnawing beak special attacks.
A fleeing octopus usually covers its escape with an ink cloud and then speeds away using its jet ability.
Chameleon (Ex): A giant blue-ringed octopus can change its colour, combined with a limited ability to alter its body-shape and texture this gives it a +8 racial bonus on Hide checks. The octopus does not need cover or concealment to attempt a Hide check if it can match the colour of its surroundings.
Gnawing Beak (Ex): A giant blue-ringed octopus can bite an opponent it is grappling as a primary attack (bite +5 melee for 1d3+1 damage plus poison) or by succeeding at an opposed grapple check (for the same damage). If the blue-ringed octopus spends a full-round attack to make the opposed grapple check, its gnawing beak damage ignores damage reduction and hardness of up to 8.
Improved Grab (Ex): To use this ability, a giant blue-ringed octopus must hit an opponent of any size with its arms attack. It can then attempt to start a grapple as a free action without provoking an attack of opportunity. If it wins the grapple check, it establishes a hold and can use Gnawing Beak.
*A giant blue-ringed octopus has a +10 racial bonus on grapple checks.
Ink Cloud (Ex): A giant blue-ringed octopus can emit a cloud of jet-black ink 10 feet high by 10 feet wide by 10 feet long once per minute as a free action. The cloud provides total concealment, which the octopus normally uses to escape a losing fight. All vision within the cloud is obscured.
Jet (Ex): An octopus can jet backward once per round as a full-round action, at a speed of 200 feet. It must move in a straight line, but does not provoke attacks of opportunity while jetting.
Poison (Ex): The bite of a giant blue-ringed octopus injects giant blue-ringed octopus venom, a lethal neurotoxin created by symbiotic bacteria in its saliva glands. This toxin permeates every organ in the octopus’s body, so anything foolish enough to eat the octopus's flesh will be exposed to giant blue-ringed octopus organ poison (merely biting the octopus will not result in poisoning if the attacker does not swallow its flesh). Fortunately, blue-ringed octopus poison is a lot less potent when ingested.
Giant Blue-Ringed Octopus Venom: Injury, Fortitude DC 17, initial damage 1d3 hours of suffocating paralysis plus 1d3 point of Dexterity damage, secondary damage increases suffocating paralysis to 2d4 hours and adds 1d4 points of Dexterity damage. The save DC is Constitution-based and includes a +6 racial adjustment.
Giant Blue-Ringed Octopus Organ Poison: Ingestion, Fortitude DC 15, initial damage 1 hour of suffocating paralysis plus 1 point of Dexterity damage, secondary damage increases suffocating paralysis to 1d4 hours and adds 1d4 points of Dexterity damage. The save DC is Constitution-based and includes a +4 racial adjustment.
The truly dangerous aspect of blue-ringed octopus poison is its suffocating paralysis effect. A creature who fails a Fortitude save against the poison start to feel the symptoms 15 minutes later. They become numb, lethargic and uncoordinated and may also tremble and/or suffer diarrhoea. The victim moves at half their normal speed and suffers a –4 penalty to attack rolls, ability checks and skill checks plus a –2 penalty to Reflex saves and damage rolls. In addition, the victim must succeed at a DC 10 Fortitude save or begin to suffer paralysis and suffocation (see next paragraph). The save must be repeated every 15 minutes, with the DC increasing by +1 for each previous success, up to a maximum equal to the poison’s DC of 17.
The paralysis follows the normal rules: the victim remains fully conscious but cannot move or act (They may experience seizure-like fits and nauseated vomiting, but are unable to move their body voluntarily). The suffocation is caused by the poison paralyzing the victim’s diaphragm and chest so they cannot draw breath into their lungs. A suffocating victim takes 1d6 points of nonlethal damage every 15 minutes. If the victim falls unconscious from this nonlethal damage, they drops to –1 hit points and are dying, they then take 1 point of normal damage per round until they suffocate to death. If no magical means of delaying or neutralizing the poison is available, the victim’s life can still be saved through artificial respiration, if another character succeeds at a DC 17 Heal check during a 15 minute suffocation period they prevent the victim taking any suffocation damage during that period. This requires continuous attention from the healer, who cannot leave the victim for more than a few rounds without rendering that period’s treatment worthless. The effects of the poison (incoordination, paralysis & suffocation) continue until the suffocating paralysis duration expires or the victim does.
A creature who is immune or resistant to paralysis (such as a true dragon) applies this immunity or resistance to the poison’s suffocating paralysis effect and only takes Dexterity damage.
Rubbery Body (Ex): The only hard part of an octopus is its beak, the rest of its body is soft flesh the animal can contort through muscular action. This allows an octopus to squeeze through tiny gaps, passing through such openings as if it were a creature two sizes smaller than its actual size. A giant blue-ringed octopus's bonelessness grants it a +10 racial bonus on Escape Artist checks.
Skills: A giant blue-ringed octopus's chameleon ability gives it a +8 racial bonus on Hide checks and its rubbery body gives it a +10 racial bonus on Escape Artist checks.
An octopus has a +6 racial bonus on Climb checks and 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. An octopus can use either its Dexterity modifier or Strength modifier on Climb checks and Swim checks, whichever is better.
Poison-Ink Giant Blue-Ringed Octopuses
The blue-ringed octopus's giant cousin can have poison ink as well, which changes the octopus's abilities as follows:
Ink Cloud (Ex): A giant poison-ink blue-ringed octopus can emit a cloud of poisonous jet-black ink 1 feet high by 1 feet wide by 1 feet long once per minute as a free action. The cloud provides total concealment, which the octopus normally uses to escape a losing fight. Any water-breathing creature that breathes in the ink cloud is exposed to the octopus's poison. All vision within the cloud is obscured.
Poison (Ex): The bite of a giant poison-ink blue-ringed octopus injects giant blue-ringed octopus venom, a lethal neurotoxin created by symbiotic bacteria in its saliva glands. This toxin permeates every organ in the octopus’s body, so anything foolish enough to eat the octopus's flesh will be exposed to giant blue-ringed octopus organ poison (merely biting the octopus will not result in poisoning if the attacker does not swallow its flesh). The affected organs include the octopus's ink sac, any water-breather that enters a blue-ringed octopus's ink cloud is affected by giant blue-ringed octopus ink toxin. Fortunately, blue-ringed octopus poison is a lot less potent when inhaled or ingested.
Giant Blue-Ringed Octopus Ink Toxin: Inhaled, Fortitude DC 13, initial damage 1d10 minutes of momentary paralysis, secondary damage increases momentary paralysis duration to 1d6×10 minutes and adds 1 point of Dexterity damage. The save DC includes a +2 racial adjustment.
Giant Blue-Ringed Octopus Venom: Injury, Fortitude DC 17, initial damage 1d3 hours of suffocating paralysis plus 1d3 point of Dexterity damage, secondary damage increases suffocating paralysis to 2d4 hours and adds 1d4 points of Dexterity damage. The save DC is Constitution-based and includes a +6 racial adjustment.
Giant Blue-Ringed Octopus Organ Poison: Ingestion, Fortitude DC 15, initial damage 1 hour of suffocating paralysis plus 1 point of Dexterity damage, secondary damage increases suffocating paralysis to 1d4 hours and adds 1d4 points of Dexterity damage. The save DC is Constitution-based and includes a +4 racial adjustment.
Momentary paralysis takes effect almost immediately; one round after failing their Fortitude save the victim suffers a –1 penalty to attack rolls, ability checks and skill checks; if the duration of the poison is measured in minutes then one minute after being poisoned the symptoms worsen, the victim can neither run nor charge and suffers a –2 penalty to attack rolls, ability checks and skill checks plus a –1 penalty to Reflex saves and damage rolls. The poison's penalties continue until the momentary paralysis duration ends. A creature who is immune or resistant to paralysis (such as a true dragon) applies this immunity or resistance to the poison’s momentary paralysis effect and only takes Dexterity damage. Penalties from ink poison's momentary paralysis do not stack with penalties from other forms of paralysis, such as those imposed by the suffocating paralysis of a blue-ringed octopus's venom and organ poison.
The truly dangerous aspect of blue-ringed octopus poison is its suffocating paralysis effect. A creature who fails a Fortitude save against the venom or organ poison at first feels identical effects to the ink toxin's momentary paralysis, but the symptoms become far worse after 15 minutes. The victim become numb, lethargic and uncoordinated and may also tremble and/or suffer diarrhoea. The victim moves at half their normal speed, can neither run nor charge and suffers a –4 penalty to attack rolls, ability checks and skill checks plus a –2 penalty to Reflex saves and damage rolls. In addition, the victim must succeed at a DC 10 Fortitude save or begin to suffer total paralysis and suffocation (see next paragraph). The save must be repeated every 15 minutes, with the DC increasing by +1 for each previous success, up to a maximum equal to the poison’s DC of 17.
The total paralysis follows the normal rules: the victim remains fully conscious but cannot move or act (They may experience seizure-like fits and nauseated vomiting, but are unable to move their body voluntarily). The suffocation is caused by the poison paralyzing the victim’s diaphragm and chest so they cannot draw breath into their lungs. A suffocating victim takes 1d6 points of nonlethal damage every 15 minutes. If the victim falls unconscious from this nonlethal damage, they drops to –1 hit points and are dying, they then take 1 point of normal damage per round until they suffocate to death. If no magical means of delaying or neutralizing the poison is available, the victim’s life can still be saved through artificial respiration, if another character succeeds at a DC 17 Heal check during a 15 minute suffocation period they prevent the victim taking any suffocation damage during that period. This requires continuous attention from the healer, who cannot leave the victim for more than a few rounds without rendering that period’s treatment worthless. The effects of the poison (incoordination, paralysis & suffocation) continue until the suffocating paralysis duration expires or the victim does.
A creature who is immune or resistant to paralysis (such as a true dragon) applies this immunity or resistance to the poison’s suffocating paralysis effect and only takes Dexterity damage.
Design Notes
There are four or more species of Blue-Ringed Octopuses (genus Hapalochlaena), all of which are extremely venomous. They are just at the size border of Diminutive and Fine and should arguably be Fine sized - many of them weigh 1 ounce or even less as adults. I ended up opting for Diminutive since I didn't want them to have AC 20, although I did give them a lower Strength than a diminutive common octopus.
A blue-ringed octopus's main claim to fame is its lethal venom. Produced by symbiotic bacteria in its saliva glands its main component is tetrodotoxin. The poison is present in every organ of the octopus's body, so eating one is inadvisable.
There is a Giant Blue-Ringed Octopus in the Creature Catalog, but this is a conversion of an intelligent underdark Magical Beast rather than a giant version of the real-world animal. It did inspire me to stat up a "more authentic" version of a giant blue-ringed octopus, which is pretty much my Octopus Redux with a poison attack bolted on.
The poison special ability is a somewhat accurate representation of the effects of tetrodotoxin. The only other design issue was deciding what Challenge Rating to make it. They are potentially really lethal but are so fragile they’re unlikely to bite more than one PC before being squashed. I eventually settled on CR 3, mainly because 3rd level is when a bard/cleric/druid/paladin gains access to delay poison which would render their poison harmless. I thought about comparing it to a trap – like the SRD’s nitharet-poisoned “doorknob smeared with contact poison” (CR 5) or “wyvern arrow trap” (CR 6) but those Challenge Ratings seemed too high (although I think the CRs of traps in 3E tend to be too high in general). I regular Blue-Ringed Octopus has a venom that’s just as lethal so arguably should have CR 3 too, but since it has no Reach with its attacks.