You'll see that the armor is just a large breast plate, literally. Since this appears to be too small for her, Ellie will have you search around the backside of the house in a green highlighted box.

Armor Upgrade - City of Ry'uul (Chapter 15) As you slay your way through Chapter 15 of Doom: The Dark Ages, you'll find a tougher demon that rewards you with an upgrade to your max armor.

Looking for the best Monster Hunter Wilds armor? These sets are some of the greatest you can grab to destroy monsters and make each hunt a breeze.