
Matthew Downie |

No such rule in Pathfinder. There may have been one in old editions D&D?
Instead there is this:
Some monsters are vulnerable to magic weapons. Any weapon with at least a +1 magical enhancement bonus on attack and damage rolls overcomes the damage reduction of these monsters. Such creatures’ natural weapons (but not their attacks with weapons) are treated as magic weapons for the purpose of overcoming damage reduction.
And:
Some monsters are vulnerable to good-, evil-, chaotically, or lawfully aligned weapons. When a cleric casts align weapon, affected weapons might gain one or more of these properties, and certain magic weapons have these properties as well. A creature with an alignment subtype (chaotic, evil, good, or lawful) can overcome this type of damage reduction with its natural weapons and weapons it wields as if the weapons or natural weapons had an alignment (or alignments) that matched the subtype(s) of the creature.

Jeraa |

3.5 had a rule for higher HD monsters bypassing DR, similiar to how enough plusses on a magic weapon bypass other DR types. Pathfinder did not retain this rule.
Got a source for that? Because I don't recall that being in 3.5 at all. As far as I am aware, the only difference between 3.5 damage reduction and Pathfinder damage reduction is the ability for higher enhancement bonus to overcome more types of damage reduction.

Vidmaster7 |

The first edition rule was something like magical creatures could affect other magical creatures but where otherwise immune if you didn't have a magical weapon with a high enough plus. In 2nd I think they got more specific where monsters needed to be of similar + magic to hit monsters with higher damage immunity (It wasn't DR until 3rd edition) I'm pretty sure that is all accurate.

Cevah |
3 people marked this as a favorite. |

Text from 2nd edition:
One obvious question that arises in the minds of those with a logical bent is "How do other creatures fight those immune monsters?" In the case of monsters, sufficient Hit Dice enable them to attack immune creatures as if they were fighting with magical weapons. Table 48 lists various numbers of Hit Dice and their magical weapon equivalents.
These Hit Dice equivalents apply only to monsters. Player characters and NPCs cannot benefit from this.
Hit Dice -- Hits creatures requiring
4+1 or more -- +1 weapon
6+2 or more -- +2 weapon
8+3 or more -- +3 weapon
10+4 or more -- +4 weapon
/cevah

![]() |

Hit Dice -- Hits creatures requiring
4+1 or more -- +1 weapon
6+2 or more -- +2 weapon
8+3 or more -- +3 weapon
10+4 or more -- +4 weapon
For anyone unfamiliar with 1st and 2nd Edition, those figures in the Hit Dice refer to the old way of describing creatures, as having a certain number of d8s, plus (sometimes) some extra hitpoints.
Most creatures didn't have a listed Con score, so the extra hps was intended to give them a leg up.
An ogre was 'Hit Dice: 4+1', meaning 4d8+1, or 5-33 hp.
A troll was 'Hit Dice: 6+3', ie 9-49 hp.
So having a friendly ogre on call could be a lifesaver.