Odds & fairness

You pick the prize you play for: a Collector Crypt pack or item. Win, and that prize is bought for you and opened, as a Collect Royale win's is. The price of a play is always shown before you pay, and is made of:

• The stake: the prize divided by what the bet pays. A bet that wins one time in two costs half the prize, one that wins one time in 36 costs a 36th of it.
• The platform fee: 10% of the stake. Part of Stashr's revenue buys back and burns the Stashr token every day.
• Costs: $0.50 for buying and sending the prize, shared out the same way as the stake (the prize over what the bet pays).
• A 2% margin for SOL's price moving while you pay (you pay in SOL at the live price).

Example: a $20.00 prize on red is a $10.00 stake + $1.00 fee + $0.25 costs.

The house vault backs every prize: a single play may be for at most 25% of what the vault has free. A payment that arrives too late to be played is refunded in full.

Classic blackjack: each player plays their own box against the dealer, however many sit at the table.

• Six decks, freshly shuffled for every round (the shuffle comes from the round's seeds, see below).
• The dealer stands on all 17s, and peeks for blackjack under an ace or a ten.
• Blackjack (a natural) pays 3 to 2: you win the prize and half your stake back.
• Double on any first two cards, after a split too. Split pairs (any two tens) up to four hands; split aces take one card each.
• No insurance, no surrender.

A won hand wins the prize (a doubled or split hand can win one prize per stake). A push gives your stake back. With perfect basic strategy these rules leave the house an edge of about 0.4% on the stake: a hand wins about 42% of the time, pushes about 8.5%, and loses about 49% (doubles, splits and 3:2 naturals make up the difference).

European roulette: one zero, 37 pockets, one bet a spin: a classic bet, or your own pick of any 1 to 18 numbers. Every bet is priced so that it returns 36/37 = 97.30% of its stake on average: the zero is the house's edge, 2.70%.

Each machine model is its own game with its own chance; the giant slot on the stage is the jackpot. A spin wins the prize when the reels stop on three of the machine's first symbol. The stake is the prize times the chance, so the spin itself has no house edge: the platform fee and costs are the only margin.

Every play against the house can be checked after the fact. Nobody, the house included, can know or change its outcome once you have paid.

1. The house commits first. When you ask for a price, the casino draws a secret random server seed for your play and shows you its SHA-256 hash (in the payment window) before you pay. The hash is recorded with the play.
2. You add your own randomness. Your play's client seed is your payment's transaction signature, made by your wallet after the hash was shown. The house can't know it in advance, so it can't pick a server seed that loses.
3. The outcome comes from both. A round's random numbers are HMAC-SHA256 keyed by its plays' server seeds, over their client seeds and a counter. They decide the pocket, the reels, or the six-deck shuffle. A roulette throw or a blackjack shoe shared by several players uses all their seeds together.
4. The seeds are published. Once the round is settled, its server seeds are made public. Anyone can check each one against the hash shown before payment, and recompute the round.

The verifier below runs in your browser, with the exact code the casino plays with. Your latest plays are listed when you're signed in, and every result has a “Verify” link.

Poker, Collect Royale (our battle royale) and Jaywalker are played between players: the house never plays a hand and never takes a side. Each seat's price is the prize shared over the seats, plus the platform's fee, shown before you pay. Poker's decks are shuffled with the server's secure random source.