Survivor’s Armor

Armor (any), very rare (requires attunement)

When your current hit points are equal to or less than half your hit point maximum while wearing this magic armor, you have resistance to bludgeoning, piercing, and slashing damage from nonmagical weapons. Last Stand. When you drop to 0 hit points while wearing this armor, you can choose to remain conscious instead. If you do so, you gain immunity to all damage, have advantage on weapon attack rolls, and weapon attacks you make deal an additional 1d8 radiant damage until the end of your next turn. If you still have 0 hit points at the end of your next turn, you fall unconscious and are dying. Once used, this property can’t be used again until the next dawn.