Anal circumference
An infamous feature of the equally infamous FATAL (Fantasy Adventure To Erotic Lechery) game, the Anal Circumference table enabled players to determine the maximum size of object their character's anus could accomodate without tearing.
Like most aspects of FATAL this is bizarre and terrible not only in concept but in execution, as the numbers the table provides make little sense.
Example Gameplay
Orc hits (in your ass), Orc2 hits (in your ass), Orc3 hits (in your ass). Roll for anal circumference.
Explanation of Gameplay
Triple anal penetration by orcs was a common, and well known, historical and realistic fact of medieval Europe. It could often prove to be F.A.T.A.L. Geddit?