Requirements: level 15+

In this event, you open chests and receive guaranteed prizes from each of them.

There are 3 types of chests. Each type of chests requires a different number of keys and brings rewards on a random basis.

1. Standard chest. You need 9 keys to open a chest and you can open 45 standard chests in total. One of these 45 chests will bring you the main reward.
 
2. Enhanced chest. You need 18 keys to open a chest and you can open up to 30 enhanced chests. Enhanced chests contain fewer decor compared to standard chests. One of the 30 chests will bring you the main reward.  The chance to get the main reward is higher in enhanced chests than in standard chests. 
 
3. Super chest. You need 27 keys to open a chest and you can open up to 15 chests. Super chests contain no small decor and more buildings sold for seasonal currency and superbucks in the game shop compared to standard and enhanced chests. One of the 15 chests will bring you the main reward. The chance to get the main reward is higher in super chests than in standard chests.
 
It is up to you to decide what chest to open: standard, enhanced or super chest. 
You do not have to stick to one type of chests, you can open any chest you wish.
 

IMPORTANT! YOU CAN ONLY GET THE MAIN REWARD ONCE!

So, if you, for instance, opened a super chest and received the main reward, you will not be able to receive it again no matter how many standard chests and/or enhanced chests you open.
As soon as you receive the main reward in one of the chests, the possibility to obtain it in any further chest becomes blocked.
You can receive the main reward by opening any type of chests, but you can only get it once during the event.
 
The main reward is Huamen Gate
size 7x7, can be placed anywhere
4200 coins, 1-3 energy, 1-3 baubles every 24 hours

Each chest can be opened with Ice Keys (9, 18, or 27)
 
There are 3 ways to get the Keys:

1. Completing quests
Key quests will appear one after the other in the menu on the left side

Bird Rescue I
Collect 11 backpacks (Summer House, Upgraded Summer House)
Collect 10 pistons (Shoe Shop, Upgraded Shoe Shop)
Collect 14 stepladders (Convenience Store, Upgraded Convenience Store) 

Bird Rescue II
Collect 23 towels (Recreational Cottage, Upgraded Recreational Cottage)
Produce 10 lots of denim (Textile Factory, Upgraded Textile Factory, Textile Megafactory)
Collect 8 screw wrenches (in friends' cities)

Bird Rescue III
Ask friends for 5 cups of camomile tea
Collect 10 lumps of sugar (Candy Factory, Upgraded Candy Factory when collecting toffee apple) 
Instruct 6 builders (College)

2. Collect profits from certain buildings:
Central Station: 1 key every 24 hours
Museum of Paleontology: 1 key every 8 hours
Jewish Museum: 2-3 keys every 24 hours
Cathedral of Saint Mary: 2-3 keys every 24 hours
Church of St. Anne in Kovel: 2-3 keys every 24 hours
 
3. Purchasing keys from a special offer
 
Unique offer: Cathedral of Saint Mary
size 6x9, can be placed anywhere
4000 coins, 1-4 energy, 2-3 keys during the promotion, 1-4 baubles every 24 hours