Difficulty Class (DC)
Also known as: DC, target number, TN, difficulty
Definition
A target number that a dice roll must meet or exceed to succeed. Higher DCs represent harder tasks. The GM sets the DC based on circumstances.
How it works in different systems
D&D 5e: DC 5=trivial, 10=easy, 15=medium, 20=hard, 25=very hard, 30=nearly impossible.
Vampire V5: Difficulty = number of successes needed, not a target number.
Call of Cthulhu 7e: No DC - roll under your skill%. GM may call for Hard (1/2) or Extreme (1/5) success.
Powered by the Apocalypse: No DC - 6- fails, 7-9 partial success, 10+ full success on 2d6+stat.
Example
“Climbing the slippery cliff is DC 15. You roll 1d20+4 (Athletics) and get 17. 17 beats 15, so you make it up safely!”
Common Mistakes
- Setting DCs too high for routine tasks (DC 30 should be near-impossible)
- Calling for rolls when success or failure doesn't matter
- Not adjusting DC for creative approaches