Seasonal summons give you five stacks of cards, at least of Rare rarity (similarly to Mistresses). Since it tends to happen during major holidays, it's also known as "Holiday Summon".
Each consecutive summon lowers the cost of the next one to a point. Prices are as follows:
Single summon: 499 / 479 / 449 for first / second / third onwards
10x summons: 4499 / 3999 / 3499
The first summon is free which gives a scaled down amount that is independent of your max League. After that what you get from a seasonal summons depend on the max league you have ever unlocked, not your current league. Seasonal summons are unlocked at League 20.
Seasonal Summons are a rare chance, that appear only a handful times on the whole year. So far, it's been seen on the following cases (from the most recent to the oldest):
2021
2nd August
Spring Equinox
Valentine's Eve
2020
Christmas
Cyber Monday
this one had 40% discount: single rolls costed 299 / 279 / 249 gems, while 10x costed 2699
Halloween
Summer Solstice
Easter
Saint Patrick's Day
Valentine's Eve
New Year's Eve
2019
Halloween
Easter
Valentine's Eve
2018
Christmas
Halloween
Probablilities
The billed drop chance for heroes by rarity:
Common: 0%
Rare: 74%
Epic: 24%
Legendary: 2% (*)
(*) at least one is granted with every 2 10x summons. Should it not happen, user can contact support specifying time and date of the summon. Starting from league 3 you have a chance to get 2 stacks of legendaries instead of 1.
Chest content per league
Max League
Rares
Epics
Legendary
Free
27-31
15-19
11-12
20-19
46-48
27-29
16
18-17
48-50
27-29
16
16
49-51
28-30
16
15
50-52
28-31
17
14
52-54
29-32
17
13
53-55
29-32
17
12
54-58
30-33
18
11
56-60
30-33
18
10
57-61
31-34
19
9
58-62
32-35
19
8
59-63
32-35
20
7
60-64
32-35
20
6
61-65
33-36
21
5
62-66
33-36
21
4
63-67
34-38
22-23
3
64-68
34-38
23-24
2
65-69
35-39
24-25
1-GM
66-70
35-39
25-27
Card Pool
Unlike other summons the Seasonal summon contain only event cards. It does not require the player to own or have any of the cards unlocked in order to get them in the summon.
Seasonal summons do not contain all event cards. List last updated to reflect Panda Joy Summon on 2020-03-26. All cards listed are confirmed drops. Cards not listed have not been confirmed to be part of the card pool.
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