windforce is approx 15%?

knockback gloves is approx 10%

nef rune is approx 20%

howltusk is approx 15%

i believe it also has something to do with enemy v enemy's lvls

but having a 6 nef rune would probably increase the % but it goes through diminishing returns so it might only be 80% or something, BTW 08 jalas is bugged for 100% kb i have one for pvm