Twice-Born Star is a craftable set available in all armor types. The 5-piece set bonus allows you to have two Mundus Stone Boons at the same time.
Twice-Born Star is part of the base game. The crafting station is located in Craglorn (Atelier of the Twice-Born Star). You can craft any armor, weapon or jewelry of this set in any motif style you know, as long as you have 9 traits researched (per item). You can trade crafted pieces to other players. Each set item becomes bound on equip.