Use 20 Scarecrow or Mad King stomps against players in PvP or WvW.
Use the limited use Scarecrow/Mad King in sPvP/WvW to finish off enemies. You can loot finisher as rare drops off Mad King’s Labyrinth. Make sure you activate the finisher in your Hero tab first after you have “consumed” them.
Unlike last year, this can be no longer be done on Sparring NPCs in the Heart of the Mists so you will need to fight real players.