Damage Reduction House Rule

[Celanian]

Right now, magic weapons with enough enhancement bonus can bypass DR.

+3 bypasses Silver/Cold Iron
+4 bypasses Adamantite
+5 bypasses Alignment

I think this is too powerful of an effect and trivializes many higher CR encounters.

My proposal is that the enhancement still bypasses DR, but the appropriate amount of the bonus is consumed in doing so. So someone with a +5 weapon would be treated as +2 if striking a monster with DR/Silver and as a masterwork weapon if striking a monster with DR/Evil. You can't lose more bonus than the DR of the monster so a monster with DR 1/Evil would only use up +1 of the weapon's bonus. Only the highest level DR counts for the purpose of this, so a monster with DR/Evil and Adamantite would reduce the weapon by +5 for this purpose, not +9.

Obviously if you have a weapon with the appropriate material/alignment, the enhancement bonus isn't reduced. IE a +4 Adamantite weapon would still remain +4 vs a monster with DR/Adamantite.

This makes higher CR monsters somewhat more powerful and rewards players who had the foresight to have a weapon of the appropriate material and/or alignment.

In practice what seems to happen is that DR seems to only rarely come into play with CR appropriate monsters given the resources of a typical party.

[Mortuum]

I foresee a problem here: Sometimes, reducing your bonus to overcome the DR will not be worth it. If the DR ignored is equal to the bonus lost, you'd be better off keeping the bonus. That way you do just as much damage and you hit more often. It's not worth it if the DR is a little higher than your bonus either. It might only be worth it against DR equal to double the bonus you pay.

This also makes weapons weaker compared to spells. Magic gets past DR automatically already, and it has its own simple way past energy resistance without any real cost (by attacking with a different energy type).

[Celanian]

Good point about the bonus. It should probably remove +1 per 2 DR that's overcome.

For the spells, it's not an issue. At medium to high CR, spells aren't doing too much HP damage relative to weapons. Where spells excel are buffing the melee classes, battlefield control, and applying status effects to the monsters. If their HP damage is slightly better relative to melee, it doesn't really matter.