Attribute Checks

To improve the consistency of dice mechanics and speed up action resolution, we use a single system of attribute checks to handle general skills and saving throws. This system is a highly-distilled version of that put forth in the Dungeons & Dragons, Third Edition game, and was directly inspired by the mechanics used in the Castles & Crusades RPG, published by Troll Lord Games.

Attribute Check Basics

Similar in practice to combat attack rolls, attribute checks are made with a 20-sided die, and high values are better than low. Each attribute check is based on one of the six character ability scores (Strength, Intelligence, Wisdom, Dexterity, Constitution, or Charisma; RC/9).Intro

An attribute check consists of two parts: the target number (TN) and the check modifier. The check modifier is added to the d20 roll, and if the modified result is equal or greater than the target number, the attribute check succeeds. For a little extra tension, the DM may rule that a natural "20" always succeeds, while a natural "1" always fails, regardless of modifiers.

Target Numbers

Target numbers are assigned by the DM and based on two components:

  1. Base Value: To keep things simple, the base value of any target number is 18 (the DM can easily make things easier or harder across the campaign by adjusting this value).
  2. Opposition Level: The level of the source or target of the attribute check. In most cases, this equals character level or monster HD. When inanimate objects are involved, use the level of the object's creator.

If the opposition level cannot be ascribed as above (because there is no easily identified level or HD involved), the DM may simply assign a target number based on task difficulty:

  • Trivial: TN 12
  • Easy: TN 15
  • Difficult: TN 18
  • Complex: TN 21
  • Arduous: TN 24
  • Formidable: TN 27
  • Impossible: TN 30

Check Modifiers

  1. Character Level: Characters perform better with experience and receive a check modifier of +1 per level up to 9th, then +1 for every three levels thereafter. This allows relatively rapid progression within most campaigns, but accounts for high-level improvement if desired.
  2. Ability Score Type: If the ability score is primary, apply +6; there is no bonus for using a secondary attribute. This reflects how well the character applies his primary attribute.
  3. Ability Score Modifier: Each ability score value is associated with a modifier; the higher the score, the more helpful the modifier. This reflects the character's raw talent in any attribute.
Ability Score Modifier
3 -3
4–5 -2
6–8 -1
9–12 0
13–15 +1
16–17 +2
18 +3

Examples

  • Mertrand is a 3rd-level magic-user who wants to identify the runes on a tomb entrance. The DM decides this is attribute check is based on INT, which Mertrand has as a primary ability score with a value of 15. The DM assigns an opposition level of 4 (reasoning that the runes were inscribed by a 4th-level cleric long ago). The target number is 22; Mertrand's check modifier is +10 (+3 for being 3rd-level, +6 for INT as primary, and +1 for his INT 15). If Mertrand's d20 roll is 12 or higher, his attempt to decipher the runes succeeds.
  • Blinky the 1st-level thief tries to pick Mertrand's pocket. This is a job for Blinky's DEX, which he possesses as a primary attribute with a value of 11. The target number is 21 (18, +3 for Mertrand's experience level). Blinky's check modifier is +7 (+1 for 1st-level, +6 for his DEX as primary, and +0 for his DEX 11). Blinky's d20 roll must be a 14 or higher.
  • Bugby the 7th-level cleric decides he's going to pick Blinky's pocket. Again, this is a DEX check, and the cleric possesses DEX 14 as a secondary attribute. Bugby's target number is 19 (18, +1 for Blinky's level) and he has a check modifier of +8 (+7 for 7th-level, +1 for DEX 14). He needs an 11 or more to succeed.

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