Is a bane weapon aligned?

[Wellby]

If you fire a demonbane weapon at a chaotic evil outsider, yes you do extra damage, but do you get past its DR 10/Good?

 

[Ashtagon]

Unless the weapon also has some form of alignment specified, it doesn't. And yes, that does mean an unaligned demonbane weapon is rather useless. However, the character may have acquired the good property from some other source, such as a class feature.

 

[Wellby]

wow, yes that is rather strange. we're in the web with the 'demon quelling sword', but in addition to having to enlarge our barbarian to use it more properly (that's fine), we now have to align weapon as well! strange.

man, every once and a while the properties of high level monks impress in surprising ways: her "permanently" good-aligned fists have come in handy!

 

[Patryn of Elvenshae]

Remember that not all demons have DR X/Good, though. Only the more powerful ones do, and, even then, the additional +2 enhancement bonus and +2d6 damage averages out to +9 damage, so that basically overcomes DR 10/Good, allowing your normal weapon damage to flow through.