The Winter Chest is a Limited Edition Chest that started on the 27th of December and ended on the 8th of January 2014. In the Winter Kings boss collection, 3 Winter Chest keys are given out if you collect all the regular boss armors. You receive 5 keys and Aegis of the Dragon+ if you get all of the epic boss plus versions and redeem it before Glacius goes away.
Winter chest has a 5x chance for a Legendary Armor or an Epic Armor, there is a new epic armor released inside called Druidic Platemail. When you open 11 chests at once you receive 5 Fire Fusion Boost Armor and when you open 40 you will receive 20 Fire Fusion Boost Armor and Armor of Phyrus+.