Gambit of an Erased Rogue Unique

I’m not game play savvy on how all the mechanics work, just a casual gamer enjoying the game and I had this drop last night: Gambit of an Erased Rogue. It has: 1 in 6 chance to take (25 to 15)% less Damage per Active Shadow (Multiplicative with other modifiers. The number of shadows multiplies the damage reduction, not the chance.)
I’m wondering if the shadow left from using shift counts towards the xp the unique gets??
Thank you for any help.

Edit: Just found out it does. It just took awhile for the first affix to show up. Then shortly another arrived.

Hey there and welcome to the forum
The Weaver Will unique gains affixes in a bit of a weird way
You have 1% chance on kill with a 15sec cooldown, if my numbers are right.
I hope you have a good time in the game