How to edit buffs/debuffs?

Hello, i have 2 questions:

1-How can buff and debuff effects be edited?
(For example i tried editing the shn files AbState and AbStateView, but i found no ways to increase the damage over time of poisons, nor the amount of defense taken away by fighter skill.)

2-How can a new type of buff/debuff be created?
(For example something that increase magical damage and decrease magical defence)

Erm well the fighter skill is controlled in the ActiveSkill.shn I'm pretty sure.

Just think your looking in the wrong place try there :D