While leveling my 2nd job to 60 I have run into alot of Dark Knight as tanks and noticed one major thing which was confusing me.....why don't they use all their abilities while fighting 3 or more mobs? Confused.....allow me to explain:

Abyssal Drain is a 15 yalm ranged ability that damages all enemies that get hit while doing around 300 damage non-crit and non buffed from Dark Arts to all enemies. So that means that with just this ability alone you are doing 900 damage to all mobs that get hit comparable to a buffed 900 damage non-crit buffed soul eater. Mind you that this is only 3 targets.....the damage is more with 3 or greater! If you place your dots on every target, place down salted earth, turn on Blood Price when you run out of mana spamming Abyssal Drain.....do you have any idea how much damage you are doing to all mobs lowering all their HP to when your dps get to them they only have little to no hp left to burn them down and also making kills so much faster? But I rarely see this on Dark Knights level 56 or above.....why? Because more of these tanks play Dark like its a melee dps and not a tank......try this combo for 3+ mob pulls yourself and you be the judge.....and mind it, keep you mana up, do Syphon Strike combo, Carve and Spit everytime your short on mana using common sense to only say that it doesnt work.