Metamorph — Adaptive Flesh-Harvester
A brilliant, self-altering aberration that learns from injury and converts living victims into nutrient slime.
The metamorph was engineered as a solution to hunger and became something far worse. Its black carapace covers a body that refuses to remain stable: limbs thicken, armour plates shift, sensory organs bloom and vanish, and wounded tissue rewrites itself to survive whatever hurt it last. Behind the animal violence is a calculating intelligence that studies prey as both threat and raw material.
At a Glance
Run It Tonight
The metamorph should change during the fight. Let the first round establish what the party does well, then make the creature answer it. Heavy melee pressure produces thicker armour; unreachable attackers provoke wings or climbing limbs; energy attacks teach the carapace what to resist. Its poison is the long-term horror, but the immediate encounter should feel like fighting something that is learning faster than the characters can settle into a routine.
Rules by Edition
Metamorph
Large Aberration, typically Chaotic Evil
AC 18; Initiative +4 (14)
HP 230 (20d10 + 120)
Speed 30 ft., Burrow 20 ft., Climb 30 ft.
22 (+6)
18 (+4)
22 (+6)
16 (+3)
16 (+3)
12 (+1)
Saving Throws Dex +9, Con +11, Wis +8
Skills Perception +8, Stealth +9, Survival +8
Senses Blindsight 30 ft., Darkvision 90 ft.; Passive Perception 18
Languages Aklo, Common; telepathy 60 ft.
CR 15 (13,000 XP); PB +5
Traits
Regeneration. The metamorph regains 10 Hit Points at the start of each of its turns if it has at least 1 Hit Point. While suffering from a disease, this trait doesn’t function.
Reactive Adaptation. After the metamorph takes Acid, Cold, Fire, Lightning or Thunder damage, it gains Resistance to that damage type until it uses this trait again. It can have only one Resistance from this trait at a time.
Disease Vulnerability. The metamorph has Disadvantage on saving throws against disease. Whenever it fails such a save, it also takes 14 (4d6) Necrotic damage as its tissues reproduce the infection faster than they can contain it.
Actions
Multiattack. The metamorph makes one Bite, two Claw and two Tentacle attacks.
Bite. Melee Attack Roll: +11, reach 5 ft. Hit: 17 (2d10 + 6) Piercing damage plus 14 (4d6) Poison damage.
Claw. Melee Attack Roll: +11, reach 5 ft. Hit: 13 (2d6 + 6) Slashing damage.
Tentacle. Melee Attack Roll: +11, reach 10 ft. Hit: 11 (1d10 + 6) Bludgeoning damage, and a Large or smaller target is Grappled (escape DC 19). The metamorph can grapple up to two creatures this way.
Conversion Venom (Recharge 5–6). One creature hit by Bite this turn makes a DC 19 Constitution saving throw. On a failed save, it is Poisoned for 1 minute and its Speed is halved. It repeats the save at the end of each turn, ending the effect on a success. A creature that remains Poisoned for the full minute begins a 24-hour transformation into nutrient slime; greater restoration, heal or equivalent magic ends the transformation before it completes.
Morphic Surge (Recharge 5–6). The metamorph chooses one adaptation, which lasts until it uses Morphic Surge again: Wings (Fly 50 ft.); Reinforced Carapace (AC 20); Predatory Limbs (one additional Claw attack in Multiattack); or Breath Gland (gains a 30-foot Cone breath action dealing 36 [8d8] Acid, Cold, Fire, Lightning or Poison damage, Dex save DC 19 for half).
Metamorph
Large aberration, chaotic evil
Armor Class 18 (natural armor)
Hit Points 230 (20d10 + 120)
Speed 30 ft., burrow 20 ft., climb 30 ft.
22 (+6)
18 (+4)
22 (+6)
16 (+3)
16 (+3)
12 (+1)
Saving Throws Dex +9, Con +11, Wis +8
Skills Perception +8, Stealth +9, Survival +8
Senses blindsight 30 ft., darkvision 90 ft., passive Perception 18
Languages Aklo, Common, telepathy 60 ft.
Challenge 15 (13,000 XP)
Traits
Regeneration. The metamorph regains 10 hit points at the start of its turn if it has at least 1 hit point. This regeneration stops while the metamorph is diseased.
Reactive Adaptation. After taking acid, cold, fire, lightning or thunder damage, the metamorph gains resistance to that damage type until this trait changes to another type.
Disease Vulnerability. The metamorph has disadvantage on saving throws against disease. Whenever it fails one, it also takes 14 (4d6) necrotic damage.
Actions
Multiattack. The metamorph makes one bite, two claw and two tentacle attacks.
Bite. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 17 (2d10 + 6) piercing damage plus 14 (4d6) poison damage.
Claw. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 13 (2d6 + 6) slashing damage.
Tentacle. Melee Weapon Attack: +11 to hit, reach 10 ft., one target. Hit: 11 (1d10 + 6) bludgeoning damage, and the target is grappled (escape DC 19) if Large or smaller. The metamorph can grapple two creatures at once.
Morphic Surge (Recharge 5–6). Choose Wings (fly 50 ft.), Reinforced Carapace (AC 20), Predatory Limbs (one extra claw during Multiattack), or Breath Gland (30-foot cone, 36 [8d8] chosen acid, cold, fire, lightning or poison damage, DC 19 Dexterity save for half). The chosen form lasts until Morphic Surge is used again.
Metamorph CR 16
XP 76,800
CE Large aberration
Init +11; Senses blindsense 30 ft., darkvision 60 ft.; Perception +28
Defense
AC 31, touch 17, flat-footed 23 (−1 size, +7 Dex, +14 natural, +1 dodge)
hp 250 (20d8+160); fast healing 10
Fort +14, Ref +13, Will +17; −4 vs. disease
Defensive Abilities adaptive resistance, fortification 50%; Vulnerable disease
Offense
Speed 30 ft., climb 20 ft., burrow 20 ft.
Melee bite +22 (2d6+8 plus poison/19–20), 2 claws +22 (1d8+8), 4 tentacles +20 (1d6+4 plus grab)
Space 10 ft.; Reach 5 ft. (10 ft. with tentacles)
Special Attacks constrict (1d6+12), overcome defenses
Spell-Like Abilities CL 20th; concentration +25; 3/day—morphic surge
Statistics
Str 26, Dex 25, Con 26, Int 17, Wis 20, Cha 20
Base Atk +15; CMB +24 (+26 trip, +28 grapple); CMD 42 (48 vs. trip)
Feats Combat Expertise, Combat Reflexes, Dodge, Improved Critical (bite), Improved Initiative, Improved Trip, Mobility, Multiattack, Spring Attack, Whirlwind Attack
Skills Acrobatics +30, Climb +29, Escape Artist +30, Intimidate +28, Perception +28, Stealth +26, Survival +28, Swim +21
Languages Aklo, Common, Protean; SQ compression
Special Abilities
Adaptive Resistance (Su). After taking weapon damage, the metamorph adapts against that damage form on its next turn, gaining DR 10/adamantine against the relevant physical type for 1 hour. After taking acid, cold, electricity, fire or sonic damage, it can instead develop immunity to that energy. It can maintain up to three such energy immunities at once; a fourth replaces the oldest.
Disease Vulnerability (Ex). The metamorph takes a −4 penalty on disease saves. A disease affecting it advances every round rather than at its normal frequency, and disease damage also staggers it for 1 round.
Morphic Surge (Sp). Three times per day the metamorph can radically alter itself, functioning as greater evolution surge on itself. Only one surge can be active at a time.
Overcome Defenses (Su). Its natural weapons alter after failing against damage reduction, allowing them to count as up to three relevant materials, alignments or magic properties needed to overcome DR. A fourth adaptation replaces the oldest.
Poison (Ex). Bite—injury; Fort DC 28; frequency 1/minute for 10 minutes; effect 2d4 Dex drain; cure 2 saves. A creature reduced to 0 Dexterity dies and transforms over 24 hours into living protein slime unless the process is stopped by an effect that cures disease or poison. The save DC is Constitution-based.
Ecology
Environment any land and underground
Organization solitary
Treasure standard
Metamorph
Large Aberration
Hit Dice 20d8+160 (250 hp)
Initiative +11
Speed 30 ft. (6 squares), climb 20 ft., burrow 20 ft.
Armor Class 31 (−1 size, +7 Dex, +1 dodge, +14 natural), touch 17, flat-footed 23
Base Attack/Grapple +15/+27
Attack bite +22 melee (2d6+8 plus poison/19–20)
Full Attack bite +22 melee (2d6+8 plus poison), 2 claws +22 melee (1d8+8), 4 tentacles +20 melee (1d6+4 plus improved grab)
Space/Reach 10 ft./5 ft. (10 ft. with tentacles)
Special Attacks constrict 1d6+12, poison, morphic surge, overcome defenses
Special Qualities adaptive resistance, blindsense 30 ft., compression, darkvision 60 ft., fast healing 10, fortification 50%, disease vulnerability
Saves Fort +14, Ref +13, Will +17
Abilities Str 26, Dex 25, Con 26, Int 17, Wis 20, Cha 20
Skills Climb +29, Escape Artist +30, Hide +22, Intimidate +28, Listen +28, Spot +28, Survival +28, Swim +21, Tumble +30
Feats Combat Expertise, Combat Reflexes, Dodge, Improved Critical (bite), Improved Initiative, Improved Trip, Mobility, Multiattack, Spring Attack, Whirlwind Attack
Environment any land or underground
Organization solitary
Challenge Rating 16
Treasure standard
Alignment usually chaotic evil
Adaptive Resistance (Su)
After the metamorph is damaged by a physical or energy form, its tissues begin rebuilding against that threat. Use the PF1e adaptive resistance above, translating Pathfinder terminology directly into the equivalent 3.5e damage reduction and energy immunity rules.
Disease Vulnerability (Ex)
The metamorph takes a −4 penalty on saves against disease. An active disease advances once per round; whenever disease damages it, the metamorph is staggered for 1 round.
Poison (Ex)
Injury, bite; Fortitude DC 28; frequency 1/minute for 10 minutes; effect 2d4 Dexterity drain; cure 2 consecutive saves. A victim reduced to 0 Dexterity dies and begins the same 24-hour conversion described in the PF1e block.
Behaviour
A metamorph is not mindless biomass. It watches, classifies and plans. It rarely trusts another intelligent creature for long because every alliance creates a new route by which it might be contained again. Powerful outsiders, aberrations or spellcasters can sometimes bargain with one, but the creature constantly tests whether the relationship still serves its survival.
Its feeding behaviour is clinical. Victims transformed into nutrient slime are stored in cool, protected spaces and sampled over time. Unusual creatures are especially prized because the metamorph regards different bodies as different flavours, textures and biological opportunities.
Signs Before Initiative
- A sealed laboratory or cellar contains barrels of living, slowly pulsing nutrient sludge.
- Predators vanish first, then livestock, then isolated people.
- Black flakes of carapace show different textures within a few yards of one another.
- A wounded survivor describes a creature growing armour against the weapon that had just hurt it.
- Ventilation shafts, drains and narrow cracks show scrape marks far too large for the openings.
- Disease wards or quarantine symbols appear around ruins that otherwise seem to have been abandoned in a hurry.
If Violence Starts
The metamorph spreads damage across several enemies rather than obsessing over one target immediately. It wants bites on as many creatures as possible, grapples anyone who could escape or cast freely, and changes its anatomy only after it has learned what the opposition can do.
It is intelligent enough to retreat. If the party discovers and exploits its disease weakness, a metamorph may abandon a lair rather than continue a fight in contaminated ground. If no such weakness is present, regeneration and adaptation reward it for extending the encounter.
Counterplay
Do not repeat the same damage type indefinitely. Once the metamorph begins adapting, vary weapons and energy forms so that its latest defence becomes obsolete. Effects that suppress healing are valuable, but disease is the true biological weakness: the creature’s extraordinary ability to replicate and rebuild tissue causes an infection to spread through it at catastrophic speed.
Keeping distance from the bite also matters. The conversion venom is more dangerous after the battle than during it, so parties that survive should still treat every poisoned victim as an urgent medical problem.
Origins and Spread
The original project was intended to create self-sustaining nutrition: living matter able to feed itself and remain useful to humanoid bodies. Combining ooze, plant and humanoid life produced a being that solved the problem in the most literal way possible. It learned to manufacture food by turning other living things into it.
Once free, the metamorph reproduced without mates. That makes every confirmed sighting a containment problem. One creature can become several; several can turn a ruin, mine or abandoned settlement into a feeding site; and planar travel allows an infestation to escape the world where it began.
Using a Metamorph in an Encounter
The charitable granary. A famine-struck district suddenly receives barrels of miraculous nutritious paste. Nobody knows where the donor is sourcing it.
The quarantine vault. An old research complex is still sealed by disease wards, but something inside has learned to burrow around the doors.
The perfect counter. A mercenary company keeps losing to a monster that becomes immune to whatever killed the previous specimen. They have not realised they are fighting the same creature each time.
The planar farm. A remote demiplane contains hundreds of transformed victims stored as living food. The metamorph visits only occasionally.
Related Creatures and Magic
Compare the metamorph with other adaptive aberrations in the Aberration Bestiary, creatures that transform bodies such as the Mind Flayer, and the wider principles of Transmutation Magic. Return to the World Bestiary for the wider monster index.
Source and Attribution
The legacy PF1e creature on this page originated with the Creature Codex Metamorph, written by demiurge1138. The earlier page also credited its illustration as “Forbidden World Tribute” by Dave Melvin. The artwork is retained here with that attribution rather than presented as site-owned art.
Rules Sources and Licensing
The PF1e block preserves the mechanics carried by the legacy page and is identified as third-party Creature Codex material. The 5.5e/2024, 5e/2014 and D&D 3.5e presentations are compatibility adaptations created for this entry and are not official versions of the Metamorph.
Because the original Creature Codex page does not itself establish a broad commercial licence on the article page, the source attribution should remain attached to this entry. A future art pass should replace the legacy film-tribute image with original site-owned artwork.