During the week of December 13, 2016 this card was available in a weekly card pack, along with Traitor's Touch and Cast Token. You can still earn the contents of that pack through weekly quests.
Scorpion Plate, in addition to 50Max Health and 715pxBasic Armor also has an Unique Active which, for 6 seconds, makes your basic attacks shred 2 15pxAbility Armor from target for 4 seconds. Consecutive hits refresh duration and shred additional 2 15pxAbility Armor.
Stacks with 15pxAbility Pen and other sources of Shred.