From NWN2Wiki
// JLR-OEI 04/03/06: This version is REPLACING the old DEPRECATED one.
// Returns Item property damage reduction. You must specify:
// - nAmount: amount of damage reduction
// - nDmgBonus: (dependent on the nDRType)
// - DR_TYPE_NONE: ()
// - DR_TYPE_DMGTYPE: DAMAGE_TYPE_*
// - DR_TYPE_MAGICBONUS: (DAMAGE_POWER_*)
// - DR_TYPE_EPIC: ()
// - DR_TYPE_GMATERIAL: GMATERIAL_*
// - DR_TYPE_ALIGNMENT: ALIGNMENT_*
// - DR_TYPE_NON_RANGED: ()
// - nLimit: How much damage the effect can absorb before disappearing.
// Set to zero for infinite
// - nDRType: DR_TYPE_*
itemproperty ItemPropertyDamageReduction(int nAmount, int nDRSubType, int nLimit=0, int nDRType=DR_TYPE_MAGICBONUS);
