I had actually contemplated the idea of causing vulnerability psychic as an extra damage mechanic for a 4e version of the soulknife (psionic striker). Instead of making psychic strike just pure bonus damage, it would set up the monster for the next set of attacks.
It could get kind of ugly with cold damage, or say radiant damage and a laser cleric, etc. But then again, there should be some sort of benefit for good party synergy.
It could get kind of ugly with cold damage, or say radiant damage and a laser cleric, etc. But then again, there should be some sort of benefit for good party synergy.