Grand Thesis of Physiology - Unique boon Misaki

"To heal is to understand life. To poison is to understand how it ends. True mastery lies in knowing that these are one and the same."

After years of experimentation, countless experiments, and an obsession with understanding the living body in all its forms, your research has reached a conclusion few believed possible. Every poison tested upon creatures, every antidote refined, every tissue sample collected from the countless beasts that have crossed your path, and every painstaking dissection has become another step toward a single realization: life itself is governed by principles that can be observed, replicated, and rewritten.

Your work has culminated in The Grand Thesis of Physiology, a body of knowledge unlike any other within Umbreath. No longer do you simply create poisons or medicines, rather you engineer biological change in itself. By isolating the physiological adaptations of living creatures and reducing them to their fundamental alchemical principles you have learned to borrow natures greatest triumphs for yourself, or to turn them against your enemies. To your allies, your formulae become miraculous enhancements beyond the reach of ordinary medicine. To your enemies, they become precise instruments of biological collapse, exploiting weaknesses hidden deep within their own anatomy.

Experimental Formulae

Your research has taught you that every living creature carries within it unique physiological adaptations that can be isolated, replicated, or dismantled through careful alchemical manipulation. At the end of a Long Rest, you can prepare Experimental Vials equal to your proficiency bonus called Umbra Vitae, each containing an unstable alchemical solution awaiting a biological catalyst. These vials remain viable until your next Long Rest.

As a free action, whenever you deal slashing or piercing damage, you may harvest a fresh tissue sample from a willing creature, a creature that has died within the last minute, or a creature you have damaged since the end of your last turn. The exact form of this sample is determined by the creature's physiology, and may include blood, muscle fibers, scales, venom, bark, crystal growths, ichor, feathers, or other biological material.

As a Bonus Action, you may combine one harvested sample with one Experimental Vial, consuming both to create one of the following Formulae.

Adaptive Formula

An Adaptive Formula isolates and recreates one of the sampled creature's physiological adaptations. When consumed by you or a willing creature, choose up to three physiological traits (cannot be repeated nor stacked) from the sampled creature's stat block. The imbiber gains those traits for 1 minute, provided they are biological in nature and the DM determines they can reasonably be replicated through physiology.

Examples include movement speeds, natural armor, damage resistances, sensory adaptations, regeneration, powerful musculature, amphibious respiration, or other traits stemming from the creature's physical anatomy. Magical, supernatural, or innate magical abilities such as Spellcasting, Legendary Resistance, Magic Resistance, Innate Spellcasting, Lair Actions, Regional Effects, and similar features cannot be replicated.

Self-Derived Adaptation
Alternatively, you may use your own blood as the biological catalyst when creating an Adaptive Formula, requiring no harvested tissue sample. When a creature consumes this Formula, it inherits your own physiological adaptations for 1 minute. The imbiber gains any damage resistances, damage immunities, condition immunities, and Constitution saving throw proficiency or bonuses that you possess, provided they originate from your own physiology rather than magical items, spells, or temporary magical effects.

Only one creature may benefit from a Self-Derived Adaptation at a time.

Degenerative Formula

A Degenerative Formula instead exploits flaws within the sampled creature's biology. When applied as one of your poisons, choose one of your known Degenerative Formulae. A Degenerative Formula can only affect creatures whose physiology sufficiently resembles the harvested sample, as determined by the DM.

The different degenerative formula you've learnt to make have the following effect:

Cellular Collapse
You destabilize the structural integrity of a creature's cells, preventing them from maintaining their natural defenses. Choose one damage type. For 1 minute, immunity to that damage type becomes resistance, resistance becomes neutral, and if the creature has neither resistance nor immunity to that damage type, it instead becomes vulnerable to it.

Hormonal Misidentification
Your formula disrupts the creature's endocrine and pheromonal signalling, causing the brain to catastrophically misidentify friend from foe. Familiar scents become threatening, trusted faces become hostile, and instinct overrides reason. For 1 minute, whenever the creature takes the attack action, every creature within its reach other than the one who applied this Formula is considered a False Threat. The affected creature immediately enters a state of Hormonal Overload. While in this state, it must use its entire Action, if able, to attack the closest False Threat within its reach, choosing randomly between equally close creatures. It cannot willingly target the creature that applied this Formula.

Alternatively, the creature may attempt to suppress its overwhelming survival instincts by making a Wisdom saving throw against your Signature Poison DC. On a success, it resists the effects of Hormonal Overload until the end of its turn. On a failure, its body floods itself with unstable toxins, it suffers 8d12 Poison damage, and must immediately use its Action to attack the closest False Threat as normal.

If there are no False Threats within its reach, the creature must immediately use as much of its movement as possible to move towards the nearest creature it can perceive, treating it as a False Threat instead. If no other creature can be perceived, it instead spends its Action attacking the air, walls, terrain, or otherwise frantically searching for the unseen danger.

At the end of each of its turns, the creature may repeat the Wisdom saving throw against your Signature Poison DC, ending the poison on a success.

Autoimmune Response
Your formula causes the body's own immune system to reject healthy tissue, mistaking healing as a foreign invader. For 1 minute, whenever the creature would regain Hit Points, it instead takes Poison damage equal to half the amount it would have regained. Additionally, it cannot gain Temporary Hit Points.

At the end of each of its turns, the creature may repeat the Constitution saving throw against your Signature Poison DC, ending the poison on a success.

Toxic Secretion
Your formula overwhelms the body's natural filtration systems, causing every biological secretion to become saturated with concentrated toxins. For 1 minute, all damage dealt by the creature's natural weapons, unarmed strikes, saliva, venom, blood, breath or similar physiological attacks becomes Poison damage, regardless of its original damage type. This Formula has no effect on manufactured weapons or magical effects that do not originate from the creature's own physiology.

Neural Excitotoxicity
Your formula interferes with the creature's synapses, preventing nerve cells from properly regulating electrical impulses. Every injury floods the nervous system with toxic neurotransmitters, causing widespread neurological damage that compounds with each successive wound.

For 1 minute, whenever a creature takes slashing or piercing damage from a weapon coated with this Formula, it gains one Hemorrhage stack (maximum 5 stacks). At the start of each of its turns, the creature takes Poison damage equal to your Proficiency Bonus × 1d12 for each Hemorrhage stack it has. 

At the end of each of its turns, the creature may repeat the Constitution saving throw against your Signature Poison DC, ending the poison on a success.

Progressive Neurological Collapse
Your formula attacks the central nervous system itself, disrupting communication between the brain and the rest of the body. Rather than shutting the body down all at once, the poison causes neurological functions to fail one by one. For 1 minute, at the start of each of the creatures turns, the DM chooses one of the following body parts to become impaired. Once a body part has failed, it cannot be chosen again. The impairment lasts for the remainder of the poison's duration, even if the creature later succeeds on its saving throw.

Sight. The creature becomes Blinded, regardless of immunity, losing all forms of vision and physiological senses based upon sight.

Limb. The chosen limb (arms or legs) becomes limp and unfunctional, unable to be used for anything until the duration expires.

At the end of each of its turns, the creature may repeat the Constitution saving throw against your Signature Poison DC, ending the poison on a success. Any body parts already impaired remain so until the poison's duration expires.

Sanguis perfectus
As a Bonus Action, you may inject yourself with an Umbra Vitae created using your own blood, sacrificing Hit Points equal to half your Hit Point maximum. This damage ignores resistance, immunity and cannot be prevented or reduced in any way.

For 1 minute, your body becomes a living vessel of concentrated toxins. Whenever you would deal Poison damage, you instead roll twice the normal number of damage dice for each separate instance of poison damage you deal. This affects only the number of damage dice rolled, not static bonuses or modifiers.

While your sanguis perfectus persists, your physiology is sustained only by the continual production of these unstable compounds. Should you die while under this effect, your cellular structure catastrophically fails. Your body immediately dissolves into a pool of highly toxic alchemical fluid, leaving no corpse behind. You cannot be restored to life by any means short of True Resurrection, Wish, or magic of comparable power, as determined by the DM.

Once you use sanguis perfectus, you cannot do so again until you finish a Long Rest.

Each Formula lasts until expended or until your next Long Rest. These formulae count as a poison for you either way. Whenever an Umbra Vitae requires a saving throw, it instead uses your Signature Poison DC unless otherwise stated.