Skip to main content

​
Crash — Money Model

“Dust Runner” is the flagship Entropy game. Its economy is simple to state and exact: RTP is exactly 96% for every cash-out target. This page proves it and documents every payment that enters or leaves the system.

​
The crash formula

Deriving the RTP for an arbitrary cash-out at multiplier m:
The (1 − edge) numerator is what makes every target identical in expectation — there is no “good” or “bad” cash-out point, only variance.

​
Round clock

Every server instance derives identical state from wall-clock time — no websockets, no round coordination. The next round rolls over automatically; a crashed round settles and moves on without rendering stale curves.

​
Bet bounds

Both currencies move real CrashVault custody, so bounds stay conservative out of the box. DUST is deliberately not a bet currency — it is the non-transferable activity score (see Stardust).

​
The money flow, end to end

​
1. Deposit (custody)

Player deposits into CrashVault themselves (ETH via depositEth(), USDG via depositToken()). The server sweeps Deposited events and credits the chip ledger minus the 1% deposit fee:
The vault always custodies 100% of assets; fee rows are ledger claims settled through the same signature-gated withdrawal flow. See The casino’s own 1%.

​
2. Betting (ledger)

Bets debit chips at bet time; the round’s stakes and payouts accrue per round row. A bet cashes out at m → payout = amount × m credited instantly in-ledger.

​
3. Settlement (the bank)

When a round settles, realized edge is booked per token:
Realized edge can be negative — when players outperform, the bank absorbs the variance honestly. Long-run, the law of large numbers drives realized edge toward the 4% house edge.

​
4. Edge routing (on-chain)

Accumulated realized edge is forwarded by the relayer:
The 50/50 split is fixed in the contract; a zero sink keeps its share as protocol revenue. This is the casino’s engine feeding the VIP pots and LP treasury directly.

​
Worked examples

Example A — 0.01 ETH bet, cash out at 2.00×:
  • P(crash ≥ 2.00) = 0.96 / 2 = 48%
  • Win: 0.02 ETH back (+0.01 profit). Lose: bet.
  • EV = 2 × 0.48 × 0.01 = 0.0096 ETH → exactly 96% RTP.
Example B — 0.01 ETH bet, cash out at 10.00×:
  • P(crash ≥ 10) = 0.096 → 9.6%
  • EV = 10 × 0.096 × 0.01 = 0.0096 ETH — identical.
Example C — a round’s edge accounting: 5 players stake 0.01 ETH each; three cash out at 1.5× (0.015 back), two bust.

​
Auth & session model

Stateless wallet signature — the client signs once per day:
The server recovers the signer and compares against the current and previous 24h window, so one signature a day suffices with no mid-game re-sign nag at boundaries. No sessions exist; every money-touching action carries the signature.

​
Withdrawal

Player signs (player, token, amount, nonce); relayer submits CrashVault.withdraw. Gasless for the player, signature-enforced on-chain — the server cannot move player funds. See Two Vaults & Custody. Next: Crash — Provably Fair.