Rolls & Checks (critical success & fail)
All dice rolls in the HTBAH-Universe are done with a D100, unless an adventure contains a different rule module.Critical success or a critical fail depends on the abilities of your Character. Those abilities show your chances to pass a check. The difference between this value and the maximum of 100 shows you the chance of failure ("inability"). The first 10% of your ability value indicate a critical success and the last 10% indicate a critical Failure.
The calculation is easier than it appears.
Here is an example:
Howky took 70 points in cutting down trees. The chance for a success is 70% (7% critical). In conclusion is the chance for failure is 30% (3% critical) If Howky has a critical success chance of 7%. Howky turns into a crazy lumberjack machine at a roll of 1-7. If Howky rolls a result above 70% the roll is a failure. A critical failure is 3%. If Howky rolls between 97 and 100 he split his shoe instead of the tree.
Important: The roll 100 (0 + 00 on a 1D100-dice) is always a critical failure. The 1 is always a critical success.