From Guild Wars 2 Wiki
Strider's Nika is a consumable which unlocks the Strider's armor skin for Nika in the Stronghold sPvP game mode.“
Double-click to consume.
Consume to unlock this unique Mist Champion skin on your account.
— In-game description
|League Vendor||Hall of Memories||Heart of the Mists|
- Black Lion Chest (historical)