Winter Glades Blitz is a special dungeon event during 2014 Christmas Event (December 23, 23:00 PST ~ December 30, 23:59 PST).
Jack Frost, Furious Nick and Snow Princess Eva are units that can only be obtained using Rare Summon Gate.
Feisty Frosty is also obtainable and appears in all levels.
The Special Dungeon will also allow you to collect the following items.
Snow Flake
Snow Crystal
Snow Gem
Miracle Frost
Frozen Heart
Frozen Soul
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