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Metamorphic Venom

Weight —; Price varies; Feats Craft (alchemy) DC equals save DC + 5


Metamorphic venom is an alchemical weapon developed by serpentfolk that changes its effect cyclically. Many variations exist and serpentfolk alchemists readily invent more as needed. Venom might be smeared on a weapon or placed on the tip of the user’s gloved finger. Most metamorphic venoms have a 3- to 7-stage cycle. The venom changes color and odor between stages, so the user can know which effect is active. The venom changes stages rather than being used up when a creature is exposed to it or it has its non-poison effect. Each exposure to a different stage of the same metamorphic venom functions as exposure to a different poison, with separate effects and saving throws. Non-poison stages do not allow Fortitude saves and simply take effect once rather than continuously.

Non-poison stages can affect creatures that are immune to poison and potentially even objects. The venom is exhausted once the final stage has been used.

Metamorphic Venom Ignition

Price 360 gp; Type poison, contact; Save Fortitude DC 13; Frequency 1/round for 2 rounds


  • First Stage (transparent): 1d2 Dex damage
  • Second Stage (red): 1d6 fire damage and victim catches on fire
  • Third Stage (non-poison; blue): douses burning on contact

Metamorphic Venom: Strike and Escape

Price 1,500 gp; Type poison, contact; Save Fortitude DC 15 Poison Frequency 1/round for 4 rounds


  • First Stage (brown): cumulative –1 penalty to attacks and Perception checks for 1 hour
  • Second Stage (gray): 1d6 acid damage; also affects worn armor and is not halved or reduced by hardness
  • Third Stage (yellow): 1d2 Con damage
  • Fourth Stage (green): 1d2 Str damage
  • Fifth Stage (blue): 1d2 Dex damage
  • Sixth Stage (non-poison; black): produces 10-ft. cube of smoke around object touched, as the spell fog cloud
  • Seventh Stage (non-poison; white): heals 1d8+1 points of damage and grants a +10 bonus on saves against exposure to prior stages of strike and escape for 4 rounds

Using Metamorphic Venom: Strike and Escape

1. First application: This weakens and deadens the target’s vision, so he cannot easily track or see the user.

2. Second application: This acid can weaken the target’s armor or other protection.

3. Third application: This poison makes other poisons more dangerous.

4. Fourth application: This poison weakens the target now that she cannot easily resist.

5. Fifth application: The third venom is applied in case the third application was resisted or ineffective or just to add more toxin to the victim to end the fight faster.

6. Sixth application: This produces a cloud of black smoke for the user to hide or flee behind.

7. Seventh application: This healing salve is supposed to be applied to the wounds the user has received in the fight. An uninjured poisoner can use it on an ally.

Section 15: Copyright Notice

Sandy Petersen’s Cthulhu Mythos, © 2017, Petersen Games; Authors: Sandy Petersen, Arthur Petersen, Ian Starcher.