The unseeing eye set question

What does the “Eye of Thaddeus” 20% chance on crit does? I can’t find it anywhere… some sites gives me wrong info about the (5) set bonus too, has this set been updated recently? I really can’t find info…

Attachment: eye.png

Bleeding damage and reduces resistance to Bleed and Pierce by 15%. Lasts for 5 seconds and it has 2 second skill recharge.

Thank u! going for it

This is on a no bleed build, damage will be higher normally.