Ring of Intrusion

Once per room, the character wearing this ring ignores any potential Damage Reduction magic or ability of the monster for the first successful attack. Thus the first successful attack causes the full calculated damage. The nature of the Damage Reduction this ring bypasses can be physical or magical/energy. E.g., it could ignore resistance to Fire attacks vs. a Fire enhanced weapon, so if the weapon caused three extra points of Fire damage per attack, but the creature was immune, on the first attack the creature would take the extra damage.

If a character can attack more than once per round (e.g., monk flurry of blows or ranger 2-handed weapon focus), only one of those attacks may be affected by this ring. If only one of the attacks hit, that is the one which is affected. If both attacks hit, the player chooses which one ignores the DR–presumably the one that is most advantageous.