After further review we have decided to move this thread to a category we think is more appropriate for this topic, as it's reporting an issue with the game.
Well that's interesting. First I've seen of this. Is it only in PVP?
Its the tri-focus passive from the Destruction Staff skill line. Its intended for PvE, but the passive ignores Battlespirit and works in PvP. The bonus from Empowered that does not work on players in PvP but is passed through the Tri-focus passive onto the player.
This can be stacked even higher. 70% empowered an additional 45% multiplicative from sets / passives for overall damage, then factor your crit damage multiplier. Run this in group, with Dark Covnergence, thrown down on NPC's and player, and proc. Instant wipe.
Players use it IC frequently, because you can cheese kills super easy with it. In fact typing this out. Im fairly certain there is another build that can exploited in a similar fashion.