Magic Damage Formula

Is there a formula that is semi-accurate (not 100% I know because there are MANY influences) that can predict how much damage you would do to a mob in a magic attack? I'm trying to maximize my nuking effectiveness by choosing the best mob.

For Example... At 52 I can two shot most things in the Foresaken Plains (the archers and gargoyles). The Shaman are either two shot or if they are the transforming type I have to "wake" them and then can two shot.

Essentially I'm trying to find mobs I can do the same thing with using math to my advantage. Any ideas/suggestions (and not the "go kill a bunch of different mobs and find out kind please...) on a rough formula for Magic Damage?

(sqrt(m atk)*power of spell)*int multipler*race mutlipler)/m def of the mob

Ty for the reply. Is there any idea (again rough) of a mob's M.Def? Or is it "somewhat similar" to what is shown in the small prima guide. Just curious. Thanks again.

go and try it :)

(sqrt(m atk)*power of spell)*int multipler*race mutlipler)/m def of the mob

Do you have a good equation for m.atk
Last one i saw didn't match what i had in-game :(

*race mutlipler)

Race multiplier?

Anyway, all your formula ******* needs (http://l2p.bravehost.com). And I would know.

Ty for the reply. Is there any idea (again rough) of a mob's M.Def? Or is it "somewhat similar" to what is shown in the small prima guide. Just curious. Thanks again.

bit of algebra should let you work out a monsters mdef if that equation is correct