|Figure 1: Histograming results initially suggests that the black D20 likes to produce a result of "18."|
The net result! The observed distribution of my Game Science D20 is about 80% likely given the expected distribution of a fair die, while the observed distribution of my black D20 is about 5% likely (see figure 2).
|Figure 2: Chi-squared test probability of the observed distribution given the expected distribution of a fair D20.|