Looking at the wiki I saw that Turgor, Thomas and others try to find out the stats for the enemies... Well, I could not resist: here's one (don't count on more ;-)) data constructor for a DoomRL monster - the former human:
Races.Add(IDFormer,'former human','former humans', NewPic('h',lightgray),
9, 6,10, 7, 10, 90, 21, 0,12, ID_Pistol,2,0,0,'former');
Yup, the sources are very poorly documented :-(. Now let's see how much of what is what you can figure out of it ^_^.
It would be nice if we had two, after all, most codes can be cracked only when there is two codes.
9, 6,10, 7, 10, 90, 21, 0,12, ID_Pistol,2,0,0,'former');
Sight, Agro sight, Health, usecost, movecost, hit%, XPvalue, First level encountered, weapon, basedamage, extra damage dice, # of sides on extra damage dice, short name would be my guess.
EDIT: Quoting: Turgor
got another idea for one of the 0's: the armor rating!
Actually, former humans never start with an armour rating, otherwise we'd be able to get green armor on level 1. They pick green armor up, this GIVES them an armor rating.