I feel like a proc and priority style play style would differentiate it quite a bit. The Trick Attack mechanic, for those of you that don't know, was a positioning mechanic whereas standing behind another player and hitting the mob would increase the damage 10 fold, placing all of its generated threat onto the player in between.

I can see trolls using this to throw aggro onto the melee dps, so it may only be feasible to allow it to work off of tanking classes, alone.

The damage should be very high, and the balancing factor would be the risk of standing in cleaving/breath range of the mob.

A combination of Trick Attack and an ability like Dodge (Evade the next three attacks), could be used in tandem to allow safe positioning of the attack.