Invulnerability Armor Enhancement, vs monsters

[Chovesh]

At what point do monsters get to overcome the "+3" armor enhancement "Invulnerability" (DR5/magic)? Is it HD, or does it specifically have to say in the stat block that their natural attacks are considered magical? (Obviously energy effects overcome DR).

Thanks!

[Charlie Bell]

Monsters can beat DR /magic if they have a special ability to overcome it (listed in their stat block, usually something like Magic Strike) or if the monster itself has DR /magic.

Universal Monster Rules on d20pfsrd.com wrote:

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.

[james maissen]

Chovesh wrote:

At what point do monsters get to overcome the "+3" armor enhancement "Invulnerability" (DR5/magic)? Is it HD, or does it specifically have to say in the stat block that their natural attacks are considered magical? (Obviously energy effects overcome DR).

Thanks!

In 1E it was by HD.

In 3E it would be by having DR/magic or in their description.

-James