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.
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.Last modified on October 6, 2026
