Presentation
A casino event. A good chance to get elemental tournament coins for free, maybe even explorer moves. Spenders can get two totems for 300$ on average.
Decide your objectives:
For the two totems, you will need 7 wins and thousands of coins. This will take several bundles
For elemental tournament coins, you should start a few games and restart on the first failure, to reach 30 winning rounds. Easy to achieve without spending
For explorer moves and other rewards, you must reach the latest rounds: this takes some luck or resources
For hero resource chests, just do nothing: your seer's coins will automatically be exchanged at the end of the event for 2 chests per 25 coins
Advices:
You can always pause your game by pressing escape, especially if you need to go get more coins to retry.
If you are aiming for a win and fail before stage 9, then it is better to simply restart the game rather than to spend. Therefore the future cost of retries will not increase, and you will shave about 32 coins per win.
Probabilities

1 win: 715 coins on average
50% chance to spend 400 to 925 coins
90% chance to spend 175 to 1400 coins
99% chance to spend 100 to 1975 coins
7 wins: 5004 coins on average
50% chance to spend 4275 to 5675 coins
90% chance to spend 3425 to 6825 coins
99% chance to spend 2700 to 8050 coins
Note: Some websites report a lower number of coins because they rely on the apparent odds shown in the UI, rather than the official probabilities listed in the the legal documents. For example, in stage 30, the game presents you with two cards, as if your odds were 50%. However, the actual probability of drawing a cursed card is 66%!
See below: Overview, Prizes, Detailled Probabilities
Quests


















Overview
30 rounds where you pick a single card out of two, three or four. Regular cards grant you a prize, while bad cards force you to stop and lose everything unless you pay an increasing fee to continue (25 the first time, 25 more every time, up to 150). On each round you can choose to leave with your prizes instead of pulling a card.
To reach the two totems, you need 7 wins, with 30 rounds each. This requires 4298 coins on average. Quests only reward 850 coins, so you can only reduce the total bill a bit.


Prizes
Green rewards (levels 1-6), average per 100 cards















Blue rewards (levels 7-12), average per 100 cards

















Violet rewards (levels 13-18), average per 100 cards

















Orange rewards (levels 19-24), average per 100 cards

















Red rewards (levels 25-30), average per 100 cards

















Grand Prize: Seer's Chest
You can choose one of the following rewards:












Detailled Probabilities
For a single win
0.03% chance to spend 25 coins
0.3% chance to spend 50 coins
1% chance to spend 100 coins
4% chance to spend 175 coins
9% chance to spend 275 coins
15% chance to spend 400 coins
18% chance to spend 550 coins
18% chance to spend 725 coins
15% chance to spend 925 coins
10% chance to spend 1150 coins
5% chance to spend 1400 coins
2% chance to spend 1675 coins
0.9% chance to spend 1975 coins
Bad cards
Here are the probabilities for each of the thirty rounds (source):
-, -, -, -, 25%
-, 25%, 25%, 25%, 25%
25.12%, -, 24%, 24%, 24%,
24%, 34.99%, -, 25%, 25%,
25%, 25%, 40.02%, -, 33.01%,
33.01%, 33.01%, 33.01%, 45%, 66%