Scavenger Hunt: Viper School Gear

In The Witcher 3, the only Viper School Gear available are 2 sword diagrams, both of which can be found in White Orchard: For the silver sword, the diagram can be found in White Orchard cemetery, in the chapel's basement. Note that the outside of the chapel is guarded by a wraith, who will retreat if you don't kill it fast enough. However, even if you do manage to kill it, another will appear (or the first if you didn't kill it) in the basement as you approach the diagram's location. Once taken out, retrieve the Serpentine Silver Sword diagram from the skeleton.
 * Viper silver sword
 * Viper steel sword

The steel sword diagram can be found near the Ransacked Village at the old watchtower (look for the bandit camp marker to the west of the Ransacked Village). You can either try to skillfully jump up the side furthest from the remains or walk around the base until you see a pile of bricks that can be climbed up. However you arrive on top of the plateau, take out the deserters here, being mindful not to fall off. Once they're all dead, look for a chest inside the ruined watchtower to find the Serpentine Steel Sword diagram.

Hearts of Stone expansion
With the Hearts of Stone expansion, new swords and a full set of Viper School Gear armor has been added to the game. However, finding these new items can be easily missed if the player skips over certain optional objectives while completing the main quests.

All the armor diagrams can be bought from Countess Mignole during the main quest, Open Sesame!. As you enter the Borsodi Brothers' Auction House as Vimme Vivaldi's guest, he'll eventually point out a number of people that you can talk to before the auction. To get the diagrams, talk to the Countess and eventually Vivaldi points out perhaps Geralt and Mignole can trade some items and a merchant icon will appear in the next conversation choice. This is your one and only chance to get all the armor diagrams (armor, boots, gauntlets, and trousers).

For the Viper venomous steel sword diagram, continue the Open Sesame! quest to the end, where you will eventually end up in a vault. The diagram will be in a chest near Maximilian Borsodi's house. Like the armor diagrams, you can't return back after you leave the vault, so make sure to grab it before you go.

The final piece of the set, the Viper venomous silver sword, does not have a diagram available. Instead, the player can retrieve this sword but only if additional steps are taken. When you've progressed to the quest Whatsoever a Man Soweth… do not head out to the temple just yet. Instead, go do the optional objectives with Shani to find and talk to Professor Shakeslock, who will give you very useful information in dealing with Master Mirror. Once that's finished up, head out to the temple and eventually Master Mirror will try to claim his prize and a timed choice will appear. Choose to help Olgierd, which will lead to Geralt challenging Master Mirror. He'll accept and then teleport Geralt to a twisted world. To find the sword, follow the steps below (as long as you don't interact with anything else in the world, you'll have plenty of time to solve the riddle and get the sword):
 * Head down the path away from the temple.
 * When the path forks, ignore the point of interest on the left-hand side and follow the fork on the right.
 * Kill the Foglet specters.
 * When the path splits again, take the left (it'll look like 3 paths, but the far left is not part of the split)
 * Continue straight along the path and go under the bridge, then take the left path. When the path splits, go right and you'll see a red glowing point of interest. Defeat the Hym specter around here. The sword is in the stone at this point of interest.

Journal entry

 * While traveling the downtrodden lands of Velen and the former Temerian border regions, Geralt found clues about the location of a set of diagrams for crafting the legendary equipment once worn by the Viper School of witchers. Motivated by curiosity and the prospect of acquiring these priceless objects, he decided to pursue this lead.


 * After a short investigation Geralt managed to acquire diagrams for every element of the Viper School's famous equipment. He also learned the tragic story of Kolgrim, a fellow witcher who died while trying to escape after being unjustly incarcerated for kidnapping a beekeeper's son.