Half-fiend. Always biological?

[redking]

Do half-fiends (https://www.d20srd.org/srd/monsters/halfFiend.htm) always have to have a biological relation to a fiendish parent on one side? For humans, it's straightforward. When a mage and a succubus have a "relationship", then progeny may be a half-fiend. Makes sense, right?

However, we know that's not how it goes down with a half-fiend mind flayer, for example. I can't imagine what use a mind flayer mage has for a succubus or how they could biologically reproduce together. Ditto for other creatures with unusual methods of reproduction.

So how are half-fiend mind flayers and other such creatures coming about? I can think of one possibility, but I'd prefer to let the discussion happen than bias it in a particular direction.

[Telonius]

Do half-fiends (https://www.d20srd.org/srd/monsters/halfFiend.htm) always have to have a biological relation to a fiendish parent on one side? For humans, it's straightforward. When a mage and a succubus have a "relationship", then progeny may be a half-fiend. Makes sense, right?

However, we know that's not how it goes down with a half-fiend mind flayer, for example. I can't imagine what use a mind flayer mage has for a succubus or how they could biologically reproduce together. Ditto for other creatures with unusual methods of reproduction.

So how are half-fiend mind flayers and other such creatures coming about? I can think of one possibility, but I'd prefer to let the discussion happen than bias it in a particular direction.

Clearly he loves her for her mind.

(I'll show myself out).

[redking]

Clearly he loves her for her mind.

(I'll show myself out).

Succubi are succulent. [I'll follow you right out].

Seriously though, this isn't Japanese anime and those mind flayer tentacles aren't doing anything reproductive. How do mind flayer half-fiends (for example) come about?

[Crake]

Life.. uh... Finds a way.

In all seriousness though (as serious as such a topic can really get), fiends are capable of breeding with anything, and those mindflayer tadpoles hatch from eggs, and those eggs need to be fertilized... So an incubus could just... inject his... reproductive materials into a hatching pool before whoever else is supposed to do it normally.

BoEF also has a pair of spells that makes a female's next birth either half fiend or half celestial, so that could be the process. Could also take a page out of unholy scion, where the baby is possessed by a fiend, but instead of manifesting it as an unholy scion, you could manifest it as a half fiend.

[Dalmosh]

Mind Flayers are parthenogenic, but sadistic and curious, so do all sorts of f'd up stuff.
Arcane Mind Flayers tend to be less reliant on their communities, so at best can tend to be more eccentric and individualistic. The extreme cases are blasphemous pariahs that become Alhoons.

Such an entity might wish to polymorph into a human and... do stuff, simply out of spite and a desire for new sensory input.

Individual illithids might enter the service of Demon Lords or Dukes of Hell, which might make this scenario more likely. I can't recall any specific examples but I'd expect there to be illithids in places like Lemoriax or Dis that might get up to such shenanigans.

Alternatively, deities like Ilsensine or Maanzecorian might have unique Outsiders in their service, that resemble illithids and duplicate their biology. As an example, I would expect that if Ilsensine's proxy Lugribossk, emplanted one of its tadpoles in a human host, this would result in a half-fiendish illithid.

[Zanos]

Not particularly helpful for exotic creatures but Nar-Fiendbond can permanently add half-fiend to any humanoid with int >=4.

[Dalmosh]

An Illithid could use the Ritual of Bonding to fuse itself with the Succubus. If it advanced to level 10 as an Acolyte of the Skin, it would become an Outsider. It's tadpoles would presumably be Outsiders too. I would rule that implanting one would produce a half-fiendish illithid, whose fiendish traits resembled those of a Succubus.

[Analytica]

The template lets us know what would happen if such an offspring were to emerge. That doesn't mean there is any actual path for it to happen. I would say for a number of "legal" base creature + template combinations that without some particularly unique chain of events, there wouldn't exist any such in the world. These are not things that have to exist somewhere, or player options, just an idea of what would happen if somehow they would come about.

Same with "simulacrum of X with template Y". Yes, that creature COULD exist. But perhaps it doesn't in this setting or campaign, and then there is nothing for you to simulacrum, even though there are rules for what it would have looked like.

EDIT: That said, there is at least a psychic power that gives you the half-fiend template temporarily, in Complete Psionic. Which an illithid could actually take.

[hamishspence]

According to BoVD (p35-36) , certain amounts of "exposure to evil" can transform the beings exposed. For a "Great and Powerful Malevolence", creatures could, depending on the circumstances, gain the fiendish template or the half-fiend template.

[spectralphoenix]

I'd chalk it up to horrible, blasphemous rituals during the spawning process and leave it at that. As for why? Maybe a power- hungry or desperate illithid colony made a deal to enhance their next generation. What could go wrong?

[Particle_Man]

Maybe come at it the other way? Start with a half-fiend X, and find a way to change the X part to Mind Flayer without losing the half-fiend template?

[Troacctid]

The short answer to your question is no. https://web.archive.org/web/20161101073937/http://archive.wizards.com/default.asp?x=dnd/sp/20031010a

[ShurikVch]

Darkness Given Hunger (Book of Vile Darkness) is Half-Fiend Advanced Black Pudding - was done by a Hezrou possessing it and zap with Imprison Possessor spell

Also, in one of adventures (IIRR, in some magazine - can't find it right now) BBEG is a Wizard (Transmuter?) who got Half-Fiend template by physically fusing a demon (IIRR, Glabrezu) into himself - (demon's body was partially visible), and he got "upgraded" version of the template - with telepathy, at-will SLAs, i. e. just like the typical demon of the kind

Ashardalon (Bastion of Broken Souls) was Red Dragon who replaced his heart with a demon (balor called Ammet; no, not a heart of balor - whole balor). See also Disciple of Ashardalon PrC (Draconomicon)

Demon's Breath drug (Dungeon #95) gives temporary Half-Fiend template to anybody (presuming no poison immunity) - but also shifts alignment to Evil for the same time, and "encourages" the worst violent behavior

Also, Greater Visage of Deity spell and Planar Embrace psionic power for Evil-aligned users

[Raven777]

Mind Flayers are parthenogenic, but sadistic and curious, so do all sorts of f'd up stuff.
Arcane Mind Flayers tend to be less reliant on their communities, so at best can tend to be more eccentric and individualistic. The extreme cases are blasphemous pariahs that become Alhoons.

Such an entity might wish to polymorph into a human and... do stuff, simply out of spite and a desire for new sensory input.

Illithid sex was not enough, you had to bring up undead Illithid sex. :amused:

[ShurikVch]

Additionally - Searing Seed spell (Dragon #300) cause birth of evil Half-Fiend copy of the target creature; works on any living creature which isn't immune to Fort saves

[Thurbane]

Not particularly helpful for exotic creatures but Nar-Fiendbond can permanently add half-fiend to any humanoid with int >=4.

Isn't there fluff that some Mind-Flayers are descended from humans? Or maybe that was a different edition?

If so, a Mind-Flayer with the Human Heritage feat could be an eligible target for the the Nar-Fiendbond spell.

[ShurikVch]

Isn't there fluff that some Mind-Flayers are descended from humans? Or maybe that was a different edition?

If so, a Mind-Flayer with the Human Heritage feat could be an eligible target for the the Nar-Fiendbond spell.
That's depend on - if Mind-Flayers are legal for Human Heritage: the feat must be taken at the 1st level; Mind-Flayers are level 15 right out of the box

[Zanos]

Isn't there fluff that some Mind-Flayers are descended from humans? Or maybe that was a different edition?

If so, a Mind-Flayer with the Human Heritage feat could be an eligible target for the the Nar-Fiendbond spell.
Depends on what you mean by 'descended'. Most mind flayers are created from implanting a tadpole into a humans specifically, since they're the most reliable hosts. That might fly with some DMs.


That's depend on - if Mind-Flayers are legal for Human Heritage: the feat must be taken at the 1st level; Mind-Flayers are level 15 right out of the box
Depends on how you rule RHD. If you say they get them all at once in some manner, then no creature with 2 or more HD can ever take a feat that requires you be first level, of which there are quite a few. Can you take a feat that requires +6 BAB with your first HD feat if your total RHD give you 6 BAB?

Although the workaround would be to level drain yourself to 1 HD and then retrain, and then get a greater restoration.

[Thurbane]

Depends on what you mean by 'descended'. Most mind flayers are created from implanting a tadpole into a humans specifically, since they're the most reliable hosts. That might fly with some DMs.

Actually, I did a bit of checking, and I was thinking of an earlier edition (Spelljammer apparently): https://en.wikipedia.org/wiki/Illithid#:~:text=This%20version%20holds%20that%20t he,underground%2C%20into%20the%20mind%20flayers.


Yet another version came from The Astromundi Cluster, a Spelljammer boxed set produced before The Illithiad. This version holds that the illithids are descended from the outcasts of an ancient human society that ruled the now-shattered world called Astromundi. The outcast humans eventually mutated, deep underground, into the mind flayers.

[hamishspence]

Actually, I did a bit of checking, and I was thinking of an earlier edition (Spelljammer apparently): https://en.wikipedia.org/wiki/Illithid#:~:text=This%20version%20holds%20that%20t he,underground%2C%20into%20the%20mind%20flayers.

In 3e (Lords of Madness), Illithids are from the far future, and have travelled back in time, and seek to ensure that the illithids will arise (creating a stable time loop).

Which results in the fanon that Illithid Heritage feats from Dragon Magazine (and Complete Psionic) don't have to represent you having ancestors who were experimented on by ilithids - that instead, they can represent you being a proto-illithid - the ancestor of true illithids:

https://tvtropes.org/pmwiki/pmwiki.php/NightmareFuel/DungeonsAndDragons

Illithids are from the distant future, where they ruled a universe of dying stars, and shunted themselves to the present time to avoid catastrophe and get jump-started on forging their empire.

This puts a disturbing twist on the "Illithid Heritage" feats available in the Complete Psionic. In most cases, Heritage Feats reflect an extraordinary ancestor like a dragon or outsider, but in the case of the illithids, it means a character may be the product of the mind flayers' sinister experiments... or, if the traits came about naturally, then they're a distant ancestor of the future illithid species.

[ShurikVch]

However, we know that's not how it goes down with a half-fiend mind flayer, for example. I can't imagine what use a mind flayer mage has for a succubus or how they could biologically reproduce together.
Illithid can implant their tadpole in the Succubus
I don't sure if it count as "reproduction", and the result would be Half-Illithid Succubus rather than Half-Fiend Mind Flayer - but, still, they do it "together"...

[hamishspence]

Underdark's Half-Illithid template is applicable to any corporeal non-construct creature - but unlike Fiend Folio's template, it is not specifically cerebremorphosis (tadpole implantation) (which, according to Lords of Madness, only works properly on humanoids). It also says that

"most often, such progeny are formed through magical tampering with the reproductive process of the host creature, rather than through direct mating".

[afroakuma]

Could just do something like having a fiend taint the brine pool in which the tadpoles are swimming with its blood or seed. No need for it to have been sexual reproduction, as long as there is clear and unambiguous exposure to the evil essence of a fiend.

[Thurbane]

Could just do something like having a fiend taint the brine pool in which the tadpoles are swimming with its blood or seed. No need for it to have been sexual reproduction, as long as there is clear and unambiguous exposure to the evil essence of a fiend.

Good point. The Unholy Scion from HoH is a variety of "half-fiend" where the template is applied in utero via exposure to Taint, so it's theoretically feasible similar could be used for Illithid tapdpoles.

[ShurikVch]

Underdark's Half-Illithid template is applicable to any corporeal non-construct creature - but unlike Fiend Folio's template, it is not specifically cerebremorphosis (tadpole implantation) (which, according to Lords of Madness, only works properly on humanoids).
Not only on humanoids - on Chuuls and Ropers too!..

[hamishspence]

Not only on humanoids - on Chuuls and Ropers too!..

I think that would come under "works, but improperly''.

For the Chuul:

"The experience invariably slays the illithid tadpole, but not before it reduces the chuul to a slimy mockery of its former existence".

The roper, however, is described as "viable" and as "the process working", true.

Both "result creatures" have unique statlines, rather than simply being "chuul with half-illithid template" or "roper with half-illithid template".

[afroakuma]

I think that would come under "works, but improperly''.

Aye, accurate, given that neither the urophion nor the uchuulon are illithids.

[Thurbane]

To be perfectly honestly, a lot of the "half-" templates make little sense if we introduce real-world/common sense biology into the equation.

How would a Half-Dragon Gelatinous Cube work, for instance?. Oozes certainly don't follow normal vertebrate reproduction methods (I say vertebrate rather than reptile, since it isn't 100% D&D canon that dragons are reptilian, AFAIK). I mean, there is variety, even in vertebrates, but nothing remotely like how Oozes work.

[ShurikVch]

I think that would come under "works, but improperly''.

Aye, accurate, given that neither the urophion nor the uchuulon are illithids.
Not according to Lords of Madness:

Urophions
The racial limitations involved in selecting donor bodies for ceremorphosis are well known to the illithids. Still, this knowledge does not prevent them from experimenting with other creatures to see what might result. In most cases, both host and tadpole die.
Oddly, implanting a tadpole into a roper proves viable. The result is a urophion, or illithid roper. This is the only known case of tadpole implantation succeeding in a cold-blooded creature.
Physically, ropers and urophions are nearly indistinguishable. Urophions are stationed around illithid communities to act as guardians and sentinels. The live their lives much as any roper would: solitary, sedentary, and stationary. Their acute senses allow them to detect intruders at great distances. When a victim approaches within 50 feet, a urophion unleashes a powerful mental blast to stun the prey, then uses its six very long tentacles (up to 50 feet in length) to grasp the victim, drag it close, and extract its brain.
Intellectually, urophions are on par with any other illithid, and their psionic abilities are nearly as powerful. Nevertheless, they are viewed by the community as a whole as inferior and suited only for lives of dreary service. Their one honor is to be offered to the elder brain upon their deaths.
Brilliant but isolated, urophions live lives of desperate loneliness and frustration. While most remain loyal to their creators, some wander away in pursuit of their own inscrutable objectives.

[afroakuma]

That quote also specifies that they are not considered to be true illithids and are in fact a different thing. Not to mention, it's also overridden within that same book by the urophion's own entry:


These miserable creatures are nearly as intelligent as their mind flayer kin

And of course urophions lack the full suite of psionic capabilities actual illithids possess, lack the external physiological changes conferred through ceremorphosis, are not noted to be capable of producing new tadpoles themselves... there's no meaningful comparison.

In any event, others who might take an interest, see the above points.

[Troacctid]

To be perfectly honestly, a lot of the "half-" templates make little sense if we introduce real-world/common sense biology into the equation.

How would a Half-Dragon Gelatinous Cube work, for instance?. Oozes certainly don't follow normal vertebrate reproduction methods (I say vertebrate rather than reptile, since it isn't 100% D&D canon that dragons are reptilian, AFAIK). I mean, there is variety, even in vertebrates, but nothing remotely like how Oozes work.
Clearly it was created by a dragon with Master of Many Form levels who transformed into an ooze and then reproduced asexually.

[Anthrowhale]

Additionally - Searing Seed spell (Dragon #300) cause birth of evil Half-Fiend copy of the target creature; works on any living creature which isn't immune to Fort saves

Wow, that's a pretty eye-popping spell. Something like Ice Assassin except that you need an extra minion methodology like Necrotic Tumor. On the plus side no xp cost, a standard action cast, and the half-fiend template. The blasphemy SLA is pretty terrifying on a high hit dice subject.

[Kalkra]

I just skimmed through the replies, so I don't know if this already mentioned, but here (https://web.archive.org/web/20160705194759/http://archive.wizards.com/default.asp?x=dnd/we/20060630a) it mentions the option of using rituals to become a half-fiend. This would presumably work for any other half-breed template.

[ShurikVch]

I just skimmed through the replies, so I don't know if this already mentioned, but here (https://web.archive.org/web/20160705194759/http://archive.wizards.com/default.asp?x=dnd/we/20060630a) it mentions the option of using rituals to become a half-fiend. This would presumably work for any other half-breed template.
Speaking of rituals: there are also Ritual of Unlearning, Ritual of Vitality, and Wish - in the Savage Species

Also, Dwiergus the Chrysalis Prince (https://forgottenrealms.fandom.com/wiki/Dwiergus) have ability to cocoon target creature to turn them into a Half-Fiend servant

Lemorian is a kind of Half-Fiend related in some way to Lemoriax city in the Gaping Maw (88th layer of the Abyss). Vanthus Vanderboren (Savage Tide Adventure Path) was originally a Human, but later in the AP acquired this template somehow

[redking]

Alright. We've established canon non-biological acquired variants (instead of inherited as normal) template half-fiends. I guess that even a mind flayer that hangs out in the abyss could have a half-fiend tadpole due to the evil abyssal radiation. I wonder if there is the fantasy equivalent of a Geiger Counter to measure it.

[Crake]

I wonder if there is the fantasy equivalent of a Geiger Counter to measure it.

The detect evil spell.

[hamishspence]

The rules don't actually say what happens when you cast the spell on one of the evil-aligned Outer Planes. "The plane itself" isn't exactly a creature or an evil magic item or a spell.

https://www.d20srd.org/srd/spells/detectEvil.htm

[Particle_Man]

I would assume that every native object/creature on an evil plane would register as evil since it is made out of evil as a building block. So perhaps “blind spots” in the spell could in effect detect non-evil non-native creatures and objects?

[hamishspence]

The Detect Evil spell specifically calls out magic items, not "regular" objects. And it's not like the tracking ability of the Stalker of Kharash (BoED) says "Completely useless on the Lower Planes" after all.

So I'd say that the density of evil radiation is even lower than Dim - too low for the spell to pick up (but high enough for social penalties to still be a thing).