Question about opportunist feat

[DemoneNero]

So the description says: "Increases damage against rooted, stunned and incapacitated targets by 25% and against slowed targets by 15% with weapons, unarmed attacks and throwing knives" now, I would like to know if it increases the damage of special bolts too, if I perform a critical (Deadly Snares) is the 25% additive or multiplicative ?
Thanks a lot in advance

[Styg]

It is multiplicative with critical damage bonus, but additive with other similar bonuses (e.g. combo, hunter, paranoia; they are all added up and then used multiplicatively with other bonus types). However, it does not affect the special bolt damage (acid, heat, and such), just the regular damage.

Hope this cleared it up for you.

[DemoneNero]

Thanks a lot