- hardly anything does more than a die of damage;
- very large humanoids do more than a die of damage if they use weapons (trolls are specifically exempted in their description because they don't use weapons;)
- very large insects/animals do more than a die of damage, as do sea monsters; these are the only creatures where increased size always means increased damage;
- elementals mostly act like very large animals, but their damage is modified by attack conditions in unique ways;
- djinn and efreet are treated like large animals as well, despite being humanoid;
- elves get a +1 to damage when using magic weapons.
|monster size (HD)|| ||damage dice+adds|
|4+1 HD to 6+ HD||1+2|
|8 HD+||1 die/ 4 HD|
|(does not apply to giant non-supernatural humanoids using natural attacks)|
Edit: Corrected damage for the 4+1 to 6+ HD size category from 1+3 to 1+2. The damage value comes from the ogre, and for some reason I thought the ogre entry said "1+3". By accident, this fits better with my house-rule that 4 static points (hp or damage) is equivalent to 1d6, which means that 3 points should be 1-1 and 2 points should be 1-2.
Breath weapons that do damage (as opposed to effects like petrifaction) can also be converted: make them behave like dragon's breath, doing 1 die of damage per HD, with the understanding that a chimera's dragon-head is only one-third of the creature, so it does HD/3 dice of damage.