User blog comment:77Luciole77/What about the drop skills?/@comment-70.67.179.223-20130626032226

The boost is calculated with the atk pwr without the effects of skills. Same with drops each skill is calculated with the initial atk pwr.

Example if you have two boost skills with a value of 25% each and a initial atk of 1000 (being hyopthetical):

(1000 x 25 / 100) + (1000 x 25 / 100) + 1000 = 1500

To simplify:

250 + 250 + 1000 = 1500

Now your ememy has two drop skills with a value of 25% each. You have 1500 from you past boost:

1500 - ((1000 x 25 / 100) + (1000 x 25 / 100)) = 1000

To simplify:

1500 - ( 250 + 250 ) = 1000

So at the end of the battle your total atk would be 1000. Notice how each skill calculation is independent and is not affected by the previous skill.