Many challenges are now listed as 'Broad'. This means the probability of success increases linearly from 0 and up, with a roof on 100%. This is different from the previous system, 'Narrow', where the challenge only increased around +/- 5 levels from the challenge level.
The probability of success for a 'Broad' challenge relies on three things: the Level of the Attribute or Quality being tested, the Difficulty Level, and the Difficulty Scaler, as follows:
- Probability of success = (Scaler) * (Quality Level) / (Difficulty Level). [rounded down]
template = Template:Calculator/Probability form = Probability result = ProbabilityResult param = quality|Quality Level||int|0-350 param = diff|Difficulty Level|50|int|1-1000 param = scaler|Difficulty Scaler (%)|60|int|1-100
The difficulty scaler for Fallen London is 0.60 (as of 9th Sept. 2013). This gives the 'base' probability of success (60%), which occurs when the Quality Level equals the Difficulty Level.
The following adjectives are used to describe the difficulty of a particular challenge, based on the calculated probability:
- 0-10%: almost impossible
- 11-30%: high-risk
- 31-40%: tough
- 41-50%: very chancy
- 51-60%: chancy
- 61-70%: modest
- 71-80%: very modest
- 81-90%: low-risk
- 91-100%: straightforward
e.g. a Broad challenge on Shadowy with a difficulty level of 50 would currently have the following chances of success:
- 0-8: almost impossible
- 9-25: high-risk
- 26-33: tough
- 34-41: very chancy
- 42-50: chancy
- 51-59: modest
- 60-67: very modest
- 68-75: low-risk
- 76+: straightforward
For further reading, this Story Nexus reference describes this rather less drily.
Work out the likely difficulty level, given your probability and quality level:
template = Template:Calculator/Difficulty Level form = Difficulty result = DifficultyResult param = quality|Quality Level||int|0-999 param = prob|Success Probability (%)|50|int|0-100 param = scaler|Difficulty Scaler (%)|60|int|1-100
Given your current probability of success, what quality level will you need to achieve your desired probability?
template = Template:Calculator/Relative Probability form = RelProbability result = RelProbabilityResult param = quality|Quality Level||int|1-250 param = prob|Success Probability (%)||int|1-100 param = prob2|Desired Probability (%)|80|int|1-100
Challenge List GeneratorEdit
template = Template:Calculator/ChallengeList form = ChallengeGenerator result = ChallengeGeneratorResult param = qualLink|Quality Link|Dangerous|string param = diff|Difficulty Level|50|int|1-1000 param = scaler|Difficulty Scaler (%)|60|int|1-100