random is god, dunno what your question was tho, since u seem to understand simple things.just look in critical_failures.fos if you want to know what roll is doing what... like decribed in the comment line in the script i guess, the rest is simple math like u already figured out.you already figured out the differences between different luck, its simple addition operationRandom(1, 100) - 5 * (cr.Stat[ST_LUCK] - 5); or Random(1, 100) + (- 5 * (cr.Stat[ST_LUCK] - 5));Random() just generates a number between 1 and 100 this value will be used for simple calculation. only thing you have to pay attention too is that a negative number multiplied with another negative number will have an positive result.you analysed that already on the bottom like, Random number between 1 and 100 + (-5*(1-4)) would look like Random + (-5*(-3)) > Random number between 1 and 100 + 15 and so on ...