Twice-Born Star is one of the craftable sets providing special bonuses to armor and weapons. It is available for crafting to players pursuing blacksmithing, clothing and/or woodworking professions. The special crafting site dedicated to creation of this set is available in Craglorn.
2 items: Adds 28-1206 Maximum Health
3 items: Adds 25-1096 Maximum Stamina
4 items: Adds 25-1096 Maximum Magicka
5 items: You can have two different Mundus Stone boons at the same time, not two of the same.