A typical stat block:

Bel, Slayer of Men HD 10 AC 2 flaming whip (no damage but on a hit it grants +4 on the hit with the sword in the same round and on a 20 it disarms the opponent) or 1 flaming sword (3d6) MV 9 SV 7 ML 12; flaming aura deals an extra 1d6 to everybody nearby; immune to non-magic weapons; immune to fire

HD are hit-dice; roll as many d8 to determine hit-points. A +1 or +2 means that the monster attacks as if it had a HD more, so it is relatively ferocious.

HD Example

AC is armor class and determines how hard it is to hit.

AC Example
9naked man
7leather armor, eg. thieves
6small and fast creatures such as goblins
5chain mail
3plate mail

What follows are all the attacks that require a to-hit roll. Special abilities and spells are listed at the end.

MV is the movement rate. Often a note is added to explain unusual values, eg. MV 15 (fly).

MV Example
15slow flying creatures
12normal clothes, leather armor
9chain mail
6plate mail
3plate mail and carrying a lot of treasure or extra equipment

SV is the saving throw. Ordinarily it is simply 19-HD, -2 if a bit more resistant to magic or otherwise tougher.

ML is the morale score.

ML Example
2animals that will always run
3animals that will fight when cornered
4herbivores defending their young
5carnivores, cowards
6cautious people
7normal men
8well led humanoids
9disciplined troops
12unnatural creatures

Alphabetical List