So I was thinking about the Tarnished Caliburn, this war's guardian bonus. It triggers on 'evil' enemies to deal void damage, but is it more effective than a light weapon with an anti-undead MC bonus? I figure that if an enemy has an elemental weakenss of 150-180, the light weapon is preferable, but what's the cut-off point?
Tarnished Caliburn deals 120% damage and inflicts a Power 2 Poison at a +0 to save, on average that adds 10% melee for a total of 130% damage. An Undead trigger is worth 10%, therefore its equivalent to Caliburn at 130/1.1 = 118.18% elemental resistance, so at and above 119% resistance an Undead trigger weapon would be stronger.