I didn't see that this is mentioned here. In MonLvl.txt all L-XX columns is used for ladder/single player and tcp-ip. So here is a fileguide for this file.
MonLvl.txt
AC: Armor Class (Normal), is calculated together with monstats.txt column(s) {(MonLvl.txt Ac * Monstats.txt AC) / 100}, Closed battle.net only
AC(N): Armor Class (Nightmare), is calculated together with monstats.txt column(s) {(MonLvl.txt Ac * Monstats.txt AC) / 100}, Closed battle.net only
AC(H): Armor Class (Hell), is calculated together with monstats.txt column(s) {(MonLvl.txt Ac * Monstats.txt AC) / 100}, Closed battle.net only
L-AC: Armor Class (Normal), is calculated together with monstats.txt column(s) {(MonLvl.txt Ac * Monstats.txt AC) / 100}, Ladder/Single player/tcp-ip
L-AC(N): Armor Class (Nightmare), is calculated together with monstats.txt column(s) {(MonLvl.txt Ac * Monstats.txt AC) / 100}, Ladder/Single player/tcp-ip
L-AC(H): Armor Class (Hell), is calculated together with monstats.txt column(s) {(MonLvl.txt Ac * Monstats.txt AC) / 100}, Ladder/Single player/tcp-ip
TH: To Hit (Normal), is calculated together with monstats.txt column(s) {(MonLvl.txt TH * Monstats.txt A1TH and MonLvl.txt TH * Monstats.txt A2TH) / 100}, Closed battle.net only
TH(N): To Hit (Nightmare) , is calculated together with monstats.txt column(s) {(MonLvl.txt TH * Monstats.txt A1TH and MonLvl.txt TH * Monstats.txt A2TH) / 100}, Closed battle.net only
TH(H): To Hit (Hell), is calculated together with monstats.txt column(s) {(MonLvl.txt TH * Monstats.txt A1TH and MonLvl.txt TH * Monstats.txt A2TH) / 100}, Closed battle.net only
L-TH: To Hit (Normal), is calculated together with monstats.txt column(s) {(MonLvl.txt TH * Monstats.txt A1TH and MonLvl.txt TH * Monstats.txt A2TH) / 100}, Ladder/Single player/tcp-ip
L-TH(N): To Hit (Nightmare), is calculated together with monstats.txt column(s) {(MonLvl.txt TH * Monstats.txt A1TH and MonLvl.txt TH * Monstats.txt A2TH) / 100}, Ladder/Single player/tcp-ip
L-TH(H): To Hit (Hell), is calculated together with monstats.txt column(s) {(MonLvl.txt TH * Monstats.txt A1TH and MonLvl.txt TH * Monstats.txt A2TH) / 100}, Ladder/Single player/tcp-ip HP: Hitpoints (Normal), is calculated together with monstats.txt column(s) {(MonLvl.txt HP * Monstats.txt minHP) / 100 and MonLvl.txt HP * Monstats.txt maxHP) / 100}, Closed battle.net only
HP(N): Hitpoints (Nightmare), is calculated together with monstats.txt column(s) {(MonLvl.txt HP * Monstats.txt minHP) / 100 and MonLvl.txt HP * Monstats.txt maxHP) / 100}, Closed battle.net only
HP(H): Hitpoints (Hell), is calculated together with monstats.txt column(s) {(MonLvl.txt HP * Monstats.txt minHP) / 100 and MonLvl.txt HP * Monstats.txt maxHP) / 100)}, Closed battle.net only
L-HP: Hitpoints (Normal), is calculated together with monstats.txt column(s) {(MonLvl.txt HP * Monstats.txt minHP) / 100 and MonLvl.txt HP * Monstats.txt maxHP) / 100)}, Ladder/Single player/tcp-ip
L-HP(N): Hitpoints (Nightmare), is calculated together with monstats.txt column(s) {(MonLvl.txt HP * Monstats.txt minHP) / 100 and MonLvl.txt HP * Monstats.txt maxHP) / 100) / 100}, Ladder/Single player/tcp-ip
L-HP(H): Hitpoints (Hell), is calculated together with monstats.txt column(s) {(MonLvl.txt HP * Monstats.txt minHP) / 100 and MonLvl.txt HP * Monstats.txt maxHP) / 100)}, Ladder/Single player/tcp-ip
DM: Damage (Normal), is calculated together with monstats.txt column(s) {(MonLvl.txt DM * Monstats.txt A1MinD) / 100 and MonLvl.txt DM * Monstats.txt A1MaxD) / 100 and MonLvl.txt DM * Monstats.txt A2MinD) / 100 and MonLvl.txt DM * Monstats.txt A2MaxD) / 100}, Closed battle.net only
DM(N): Damage (Nightmare), is calculated together with monstats.txt column(s) {(MonLvl.txt DM * Monstats.txt A1MinD) / 100 and MonLvl.txt DM * Monstats.txt A1MaxD) / 100 and MonLvl.txt DM * Monstats.txt A2MinD) / 100 and MonLvl.txt DM * Monstats.txt A2MaxD) / 100}, Closed battle.net only
DM: Damage (Normal), is calculated together with monstats.txt column(s) {(MonLvl.txt DM * Monstats.txt A1MinD) / 100 and MonLvl.txt DM * Monstats.txt A1MaxD) / 100 and MonLvl.txt DM * Monstats.txt A2MinD) / 100 and MonLvl.txt DM * Monstats.txt A2MaxD) / 100}, Closed battle.net only
DM(H): Damage (Hell), is calculated together with monstats.txt column(s) {DM: Damage (Normal) is calculated together with monstats.txt ac column {(MonLvl.txt DM * Monstats.txt A1MinD) / 100 and MonLvl.txt DM * Monstats.txt A1MaxD) / 100 and MonLvl.txt DM * Monstats.txt A2MinD) / 100 and MonLvl.txt DM * Monstats.txt A2MaxD) / 100}, Closed battle.net only
L-DM: Damage (Normal), is calculated together with monstats.txt column(s) {(MonLvl.txt DM * Monstats.txt A1MinD) / 100 and MonLvl.txt DM * Monstats.txt A1MaxD) / 100 and MonLvl.txt DM * Monstats.txt A2MinD) / 100 and MonLvl.txt DM * Monstats.txt A2MaxD) / 100}, Closed battle.net only
DM: Damage (Normal) , is calculated together with monstats.txt column(s) {(MonLvl.txt DM * Monstats.txt A1MinD) / 100 and MonLvl.txt DM * Monstats.txt A1MaxD) / 100 and MonLvl.txt DM * Monstats.txt A2MinD) / 100 and MonLvl.txt DM * Monstats.txt A2MaxD) / 100}, Ladder/Single player/tcp-ip
L-DM(N): Damage (Nightmare), is calculated together with monstats.txt column(s) {(MonLvl.txt DM * Monstats.txt A1MinD) / 100 and MonLvl.txt DM * Monstats.txt A1MaxD) / 100 and MonLvl.txt DM * Monstats.txt A2MinD) / 100 and MonLvl.txt DM * Monstats.txt A2MaxD) / 100}, Ladder/Single player/tcp-ip
DM: Damage (Normal), is calculated together with monstats.txt column(s) {(MonLvl.txt DM * Monstats.txt A1MinD) / 100 and MonLvl.txt DM * Monstats.txt A1MaxD) / 100 and MonLvl.txt DM * Monstats.txt A2MinD) / 100 and MonLvl.txt DM * Monstats.txt A2MaxD) / 100}, Ladder/Single player/tcp-ip
L-DM(H): Damage (Hell) , is calculated together with monstats.txt column(s) {(MonLvl.txt DM * Monstats.txt A1MinD) / 100 and MonLvl.txt DM * Monstats.txt A1MaxD) / 100 and MonLvl.txt DM * Monstats.txt A2MinD) / 100 and MonLvl.txt DM * Monstats.txt A2MaxD) / 100}, Ladder/Single player/tcp-ip
DM: Damage (Normal) is calculated together with monstats.txt ac column {(MonLvl.txt DM * Monstats.txt A1MinD) / 100 and MonLvl.txt DM * Monstats.txt A1MaxD) / 100 and MonLvl.txt DM * Monstats.txt A2MinD) / 100 and MonLvl.txt DM * Monstats.txt A2MaxD) / 100}, Ladder/Single player/tcp-ip
XP: Experience Points (Normal) , is calculated together with monstats.txt column(s) {(MonLvl.txt XP * Monstats.txt Exp ) / 100 }, Closed battle.net only
XP(N): Experience Points (Nightmare) , is calculated together with monstats.txt column(s) {(MonLvl.txt XP * Monstats.txt Exp) / 100 }, Closed battle.net only
XP(H): Experience Points (Hell) , is calculated together with monstats.txt column(s) {(MonLvl.txt XP * Monstats.txt Exp ) / 100 }, Closed battle.net only
L-XP: Experience Points (Normal) , is calculated together with monstats.txt column(s) {(MonLvl.txt XP * Monstats.txt Exp ) / 100 }, Ladder/Single player/tcp-ip
L-XP(N): Experience Points (Nightmare) , is calculated together with monstats.txt column(s) {(MonLvl.txt XP * Monstats.txt Exp) / 100 }, Ladder/Single player/tcp-ip
L-XP(H): Experience Points (Hell) , is calculated together with monstats.txt column(s) {(MonLvl.txt XP * Monstats.txt Exp ) / 100 }, Ladder/Single player/tcp-ip