Checks and Opposed Rolls

Stat-Related Rolls

The following rolls may be called for by either the GM or Player:

  • Idea Roll: represents hunches and the ability to interpret the obvious.
  • Luck Roll: did the investigator bring along some particular piece of gear? Did they step on a floor board that squeaks?
  • Know Roll: represents what’s stored as intellectual “trivia” or other miscellaneous known facts.

Ability Rolls

Ability rolls are d100 rolls against a particular ability score. Sanity Checks and Attacks are examples. Success is a roll equal to or less than the ability score.

Resistance Rolls

Resistance rolls are d100 rolls that pit one characteristic against another. A player trying to open a stuck door is an example. Success is a roll equal to or less than the value from the Resistance Table, which can also be calculated as follows:

Base Chance = 50%
plus Active Characteristic x5 (e.g., player’s STR)
minus Passive Characteristic x5 (e.g., door’s stuck STR)


Example 1: a player with STR 14 vs. a door stuck with STR 12.

50 + ((14 – 12) x 5) => requires 60% or less to succeed

Example 2: a Monster with POW 16 casting a spell against a player with POW 10.

50 + ((10 – 16) x 5) => requires 20% or less to resist

Opposed Rolls

Opposed rolls are d100 rolls that pit one character’s skill against another’s. A Spot Hidden vs. Hide is an example. Opposed Rolls are resolved in the following manner:

  • Opposed rolls only matter if both characters succeed, unless some other factor automatically provides a bonus.
    • Character is attempting to hide behind a desk with a Hide of 50%. He rolls 67; a failure.
    • A character attempting to spot the hiding character automatically succeeds.
  • Opposed rolls matter if some other factor automatically provides a bonus.
    • Character is attempting to hide in a dark cemetery behind a tall tombstone.
    • The darkness and tombstone provides a +30% to Hide.
    • The character has 50% Hide, for a total of 80%, but rolls 92% – a failure.
    • An Opposed Spot Hidden is still needed, but success is based solely on the Spot Hidden characteristic.
    • A character attempts to spot the hiding character in the darkness with a Spot Hidden of 40%. He rolls 39%, which is a success, so he spots the character.
  • If both characters succeed, then the winner is the one with the highest degree of success.
    • Character is attempting to hide behind a desk with a Hide of 50%. He rolls 32; a success that creates an 18% difficulty (50-32).
    • A character is attempting to find the hiding character with a Spot Hidden of 70%. He rolls 65; a success that resolves to 5% (70-65).
    • Even though he succeeded, he fails to spot the hiding character because his 5% does not meet the 18% difficulty.
  • If both characters succeed and one has rolled a natural 1%, it is an automatic success over the opposed roll.
    • Character attempts to hide in a dark cemetery behind a tall tombstone that adds +30% to Hide.
    • Character has 50%, for a total of 80%. He rolls an 11; a success that creates a difficulty of 69%.
    • A character is attempting to find the hiding character with a Spot Hidden of 40%. (The lowest possible roll provides only 39% success value (40-1), so there is typically no possibility for success.)
    • The character rolls 01, which is an automatic success against the difficulty, so the character spots the hiding character.

Checks and Opposed Rolls

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