The description says "while using dark magic abilities increases critical strike chance by 7% when attacking targets affected by dark magic".

My question is do you get the crit bonus only for using dark magic spells ( I guess only crystal spell) on top of other dark magic spells? I'm guessing not, as this would make it petty useless. Another side question, if another sorcerer with exploitation uses a dark magic spell like rune prison or restraint prison, will other players benefit from exploitation crit bonus when using melee or non dark magic skills? Thanks in advance to anyone who can explain this.