Viper Venomous Steel Sword is one of the new armors and weapons added in the new Witcher 3 expansion - Hearts of Stone. To find this weapon, you need to find the diagram here is how you'll get Viper Venomous Steel Sword in The Witcher 3 DLC Hearts of Stone.
New Moon Armor Set can be obtained by collecting 4 pieces of the diagram and then building it. This Witcher 3 Guide will show you where to get the hidden pieces and how to build the New Moon Armor set in the game.
I Wore Ofieri Before It Was Cool is a Trophy/Achievement in the expansion of the Witcher 3 - Hearts of Stone. This Guide will show you how to unlock the Trophy/Achievement in The Witcher 3 DLC Hearts of Stone.
To get Ofieri Armor set you need to find 4 pieces of Ofier gear and four diagrams which are in foreign languages. Here is how you will find the Ofieri Armor diagram location and how to built one in The Witcher 3 DLC Hearts of Stone.