Core Dice Mechanics
AxiomRPG uses pools of six-sided dice (D6) to determine success when a character's actions are Challenged. If there is no consequence for failing to accomplish a task, no roll is required.
Because all dice are the same type, rule notation only lists the number of dice required e.g. 2D, 3D, 4D, etc.
Dice Pools are created by combining an Attribute value with an appropriate Talent value. A Talent Focus might also add dice if it applies to the action.
Example
A character with Speed 3D and Stealth 2D would roll 5D when trying to sneak.
Success
Each die showing 5 or 6 counts as 1 success.
Resolution
Compare the number of successes rolled to the task's Threshold.
- Meet or exceed the threshold = Success
- Below the threshold = Failure
Thresholds
Each Challenge has a Threshold. This is how many successes a dice pool must roll to successfully complete the task. If no Threshold is provided for a Challenge, use the Standard difficulty.
Success probability based on Dice Pool size:
| Difficulty | Threshold | 6D Pool | 9D Pool | 12D Pool |
|---|---|---|---|---|
| Easy | 1 success | 95% | 99% | 99%+ |
| Standard | 2 successes | 75% | 90% | 97% |
| Difficult | 3 successes | 45% | 65% | 85% |
| Hard | 4 successes | 20% | 40% | 65% |
| Epic | 5+ successes | 8% | 20% | 45% |
Dice Pool Modification
The number of dice in a pool can be modified by several situations and circumstances.
Bonus
Add one or more Dice to the Dice Pool.
- Bonuses are often provided by equipment, assistance or other beneficial circumstances
Penalty
Remove one or more Dice from a Dice Pool.
- Penalties are often applied by things like complexity ratings (e.g. locks), health conditions or other circumstances.
Advantage/Disadvantage
Advantage or Disadvantage is determined and applied before the dice pool is rolled.
Advantage means Success is 4+ instead of 5+.
- This can be a reflection of some beneficial circumstance increasing the chance for succeeding at a challenge.
Disadvantage means Success is 6.
- This can be a reflection of some detrimental circumstance decreasing the chance for succeeding at a challenge.
Wild Die
Every Challenge roll includes exactly one Wild Die. The Wild Die operates normally for success counting. It triggers two specific conditions based on the rolled result.
Explosion
When the Wild Die rolls a 6, it counts as 2 successes.
Implosion
When the Wild Die rolls a 1, remove 1 success from the total.
Critical Triggers
Optional Rule
The double gated Critical Trigger can be missed during the heat of play. Players have to recognize, apply and manage the variables in addition to everything else happening during a scene. While not an overly complex mechanic, it does add more crunch to a system we intended to be lighter. We present the mechanics here as an option for those GMs that prefer it.
Critical Success
A Critical Success occurs when the overall Challenge succeeds AND the Wild Die shows a 6.
In combat, the GM can select one of the following effects:
- Double the damage dealt to the target
- Gain Advantage on the next attack roll against the same target
- Create an immediate Opportunity Attack against one adjacent secondary target
In non-combat Challenges, the success produces an enhanced outcome appropriate to the action:
- Reduce the action's economy cost (Primary Action becomes Minor; Minor becomes Free)
- Improve the quality of the result (discover additional information, restore extra Health, achieve a more favorable social outcome)
Critical Failure
A Critical Failure occurs when the overall Challenge fails AND the Wild Die shows a 1.
In combat, the GM can select one of the following complications:
- The character drops (minor action to retrieve) or damages their weapon (-1D on attack rolls till repaired)
- The attack strikes an adjacent ally, dealing the roll's full damage
- The character loses footing and falls Prone (minor action to stand up)
In non-combat Challenges, the failure produces a complication tied to the action's context:
- Disadvantage on any immediate second attempt
- A secondary consequence is triggered (an alarm is raised, false information is accepted as true, a Kit's bonus die is consumed without effect)
Individual Challenges
Individual Challenges involve a character rolling their Dice Pool to generate enough successes to meet or exceed the Threshold.
Example
- A character wants to tumble past an opponent within melee range.
- This action would normally provide the opponent with an opportunity attack.
- The GM sets the Threshold at 3 (Standard Difficulty 2 + 1 for an active opponent).
- The character has Speed 3 and Acrobatics of 2. The character rolls 5 dice.
- The roll results in: 5, 3, 5, 5, 4 providing 3 successes
- The character successfully tumbles past their opponent without being attacked.
Group Challenges
Under certain circumstances an entire party may need to succeed at a Challenge. This can be accomplished using the following method.
- Each character rolls the Challenge individually
- The majority of the party must succeed for the group to succeed
- Example scenarios include stealth, climbing dangerous terrain, survival, etc.
Example
- A party of 4 characters tries to sneak past guards.
- If 3 of 4 characters succeed on a Stealth Challenge, the group gets past undetected.
- If only 2 characters succeed on a Stealth Challenge, the group is detected.