Disgeist Non-Combat Formula
I'm currently using version r18887
Mafia's non-combat calculation for the Disgeist familair seems to be using an inverse Hound Dog formula decreasing combat by floor(weight/6). The wiki shows the calculation as decreasing by floor(weight/7.5) which is backed up by the current PVP mini showing non-combat chance. The cap for the two familiars is also different, the Hound Dog caps at +5% while the Disgeist caps at -10%
For example a 33lb Disgeist and no other combat chance effects shows -5% in mafia, but the PVP mini lists it at -4%. At 76lbs mafia shows -5% and the PVP mini shows -10%.