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Mystery Warrior (3pp)

Mystery warriors train to appear suddenly, achieve their goals, and leave with no proof of their exploits. Behind them linger only wondering rumors and people safe from threats they might never have even been aware of.

Mystery warriors are meticulous about gathering information on their foes, who are often elusive or outright alien. This demands they master a variety of skills and at least dabble in the mystic arts to avoid being defeated by measures they don’t understand.

Bonus Proficiencies

When you choose this archetype at 3rd level, you either learn one language of your choice or gain proficiency in one tool of your choice. You also gain proficiency in one skill of your choice: Arcana, Deception, History, Insight, Investigation, Perception, Religion, Stealth, or Yog-Sothothery.

Paranormal Investigator

Starting at 3rd level, you can cast detect magic and identify, but only as rituals. In addition to learning how to use an item you identify, you also learn one of the following: the creator’s alignment, the purpose the item was created for, or the creator’s species.

Deduce Weaknesses

Starting at 3rd level, you can use a bonus action to add your Intelligence or Wisdom modifier (whichever is higher, minimum +1) to weapon damage rolls until the end of the current turn. When you hit a creature with a weapon attack during this time, you learn one of the creature’s traits, actions, senses, damage vulnerabilities, resistances, or immunities. The GM chooses which information you gain, but you can request one type to prioritize.

This effect is disorienting to the creature you hit. If the target creature must make a Constitution saving throw to maintain concentration as a result of this damage, it makes that save with disadvantage. If the target creature is grappling another creature, the grappled creature can use its reaction to make an ability check to escape.

You can use this feature three times. You regain all uses when you finish a long rest.


Starting at 7th level, you are mindful of your every thought and action, careful not to give away anything to your enemies.

You gain proficiency in your choice of either Wisdom or Intelligence saving throws.

In addition, you add your proficiency bonus to any ability check to conceal your presence, identity, or intentions.

If you are already proficient in the relevant skill, double your proficiency bonus on this check. For example, this includes Dexterity (Stealth) checks, Charisma (Deception) checks, and Intelligence checks with a disguise kit (if you are proficient).

Rote Reconnaissance

Starting at 10th level, you can use the Disengage, Hide, Search, or Use an Object action as a bonus action.

Coordinated Strike

Starting at 10th level, when you take the Attack, Dash, Hide, Search, or Use an Object action, an ally of your choice that you can see or hear and that can see or hear you (before or after you act) can use their reaction to take the same action. If an ally takes the Attack action this way, they can only make a single attack, even if they could ordinarily make multiple attacks with the Attack action. You can’t use this feature in the same round you use Action Surge. Once you use this feature, you can’t use it again until you finish a short or long rest.

Starting at 18th level, you can use it twice before a rest, and each time you use it, you can choose up to ten allies and allow them to use their reaction this way.

Use Magic Device

Starting at 15th level, you have learned enough about the workings of magic that you can improvise the use of items even when they are not intended for you. You ignore all class, race, and level requirements on the use of magic items.

Tactical Speed

Starting at 18th level, you can use the Attack (one weapon attack only) action or Dash action as a bonus action.

Section 15: Copyright Notice

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