Acid Blood Curse

6th-level transmutation (formula)

Casting Time: 8 hours every 10 days for 50 days (8-hour phases when cast as a formula)

Range: Touch

Components: V, S, M (rare herbs and oils worth 10,000 gp, which the spell consumes), SC (target)

Formula Ability Checks: Intelligence with alchemist’s supplies DC 17, Wisdom (Medicine) DC 17, Intelligence with alchemist’s supplies or Wisdom (Medicine) DC 18

Formula Backlash: Two levels of exhaustion

Formula Failure: 6d4 acid damage

Duration: Instantaneous

You protect a humanoid creature you touch from acid using Tcho-Tcho alchemical techniques. You also turn the target’s blood and bodily fluids highly acidic, such that they damage and corrode any material they drip upon. The target gains resistance to acid damage. The subject’s highly acidic blood damages weapons that penetrate the skin. Creatures that deal piercing or slashing damage to the subject with melee attacks take 1d6 acid damage from blood spatter. Slashing and piercing weapons that damage the target also corrode unless they are magical. After dealing damage, a nonmagical weapon takes a permanent and cumulative –1 penalty to damage rolls; when this penalty reaches –5, the weapon is destroyed. While these advantages are significant, the disadvantages are why it is called a curse. The victim’s other body fluids are also acidic, though not to the same degree as the victim’s blood. Any sweat will, over time, tatter and ruin all worn clothing, and any saliva will eventually tarnish and destroy eating utensils. This effect also makes it hard for the victim to have any intimate relationships except with another subject of the acid blood curse.

Any armor the victim wears degrades over time. At the end of every 10 days of regular use, the armor’s AC is permanently reduced by 1 unless the armor is magical.

When this reduces the armor’s AC to 10, it is destroyed. If the subject takes piercing or slashing damage, any worn nonmagical armor’s AC is reduced by 1 immediately.

The Tcho-Tcho typically bestow the curse on operatives who do not normally wear armor, and usually only on Okkators whose missions don’t involve infiltration, because the curse prevents them from being able to interact easily with society.

You need not follow any of the restrictions of spellcasting during the breaks in this spell’s casting time. If you cast the spell normally, you only expend the spell slot when you finish the casting time. (You can use that slot normally in the interim.)

Section 15: Copyright Notice

Sandy Petersen’s Cthulhu Mythos, © 2018, Petersen Games; Authors: Sandy Petersen, David N. Ross, James Jacobs, Arthur Petersen, Ian Starcher.

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