SRD:Penetrate Damage Reduction

Penetrate Damage Reduction [Epic]
Select a special material, such as adamantine.

Benefit
The character's melee weapons (including natural weapons) are treated as being crafted from the chosen special material for the purposes of bypassing the damage reduction of any creature the character strikes. None of the other special properties of special materials are gained by the character’s melee weapons.

Special
A character can gain this feat multiple times. Each time the feat is selected the character selects a different special material. The character’s melee attacks are treated as being crafted of all chosen materials for the purposes of bypassing damage reduction.