Ok, this came up in our last session and caught some of us by surprise. So we made a quick ruling on it, but I told the GM I would throw it here for confirmation.
Characters (or creatures) with DR x/Evil (where lets say x = 5) is not by-passed by just an evil NPC, just because he is evil.
The NPC (that is evil) must have an weapon that has an evil aligned weapon to bypass that.
An Evil Outsider would also by-pass the DR x/Evil with it's natural attacks.
What about DR x/Magic? Does a Magical Beasts natural weapons automatically by-pass DR x/Magic?
Characters (or creatures) with DR x/Evil (where lets say x = 5) is not by-passed by just an evil NPC, just because he is evil.
The NPC (that is evil) must have an weapon that has an evil aligned weapon to bypass that.
An Evil Outsider would also by-pass the DR x/Evil with it's natural attacks.
What about DR x/Magic? Does a Magical Beasts natural weapons automatically by-pass DR x/Magic?