lv_bonus_rate=1

hmm how this can affect the skill?

 

it increases the chance of skill landing based on level difference
if target is 70lvl and caster is 75lvl then lv_bonus_rate=2 gives 10% bonus to skill landing chance

 

so it would be

(target level - caster level) * lv_bonus_rate

??

also can it be lv_bonus_rate=-2?

 

i am not sure, probably it is (target level - skill magic level) * lv_bonus_rate
and i have never tried to use negative numbers for this property