Use the controls to play. Read the exact rules, mathematical limits, and wallet facts below.
Game Rules & Mechanics
Copy Head uses eight fair binary symbols (0 or 1). The game processes the sequence from left to right.
- Scanning: At each unread position, the game finds the longest matching substring contained wholly in the already consumed prefix.
- Capture: A match length of at least two is a copy token. Otherwise, one literal is consumed.
- Raw Score: The total of all copied lengths minus one for each copy token.
- Zero Score: Powers one, two, and three do not alter which raw scores are zero.
Stake & Mode: One whole captured stake covers this complete independent fair binary word. You choose between three modes: Score, Score Squared, or Score Cubed. Each mode is separately normalized over all 256 equally likely words.
Payout & Expected Return
The gross payout is calculated using the following formula:
| Component | Value |
|---|---|
| Expected Gross RTP | 96% |
| Exact Mean (Power 1) | 2.1015625 |
| Exact Mean (Power 2) | 4.9140625 |
| Exact Mean (Power 3) | 12.4609375 |
Gross = 0.96 × captured whole stake × raw^(selected mode + 1) / mean[selected mode]
Expected gross return is 96%; this is not guaranteed net profit. Simulation measurements are supporting sample observations, not the mathematical payout law.
The formula uses mode index 0, 1 or 2 for Score, Squared or Cubed respectively; the exponent is therefore 1, 2 or 3.
Controls & Auto Play
- Auto10: Queues at most ten captured draws.
- Stop: Cancels future draws while the current one settles.
- Settlement: 480ms captured settlement.
- Locked Controls: Stake, mode, and refill are locked through active settlement and any auto queue. Sound remains available.
No early bank is available. No independent row shares exist; one whole captured stake is used.
Wallet & Persistence
- Initial Balance: 1000 virtual coins.
- Restoration: Manual idle-only restoration. Eligible while idle and balance below 10. It sets the balance to exactly 1000 and preserves fractional carry.
- Fractional Carry: Persists across settlement, refill, and reload.
- Settled Balance: Persists locally, including zero.
- Reload: Ends an unfinished draw without refund or resume.
Mathematical Evidence
The following table shows exact expected gross RTP versus measured RTP from 1,000,000 rounds per mode.
| Mode (Power) | Exact Gross RTP | Measured RTP |
|---|---|---|
| 1 | 0.96 | 95.97818765934089 |
| 2 | 0.96 | 95.93182992690092 |
| 3 | 0.96 | 96.0172301654321 |
Fractional carry and gross-versus-net wording follow the actual contract. Simulation measurements are supporting sample observations, not the mathematical payout law.
Worked Examples
These are exact results from the actual game.js pure score function:
- Input: [0,0,0,0,0,0,0,0] → Raw Score: 4
- Input: [1,1,1,1,1,1,1,1] → Raw Score: 4
- Input: [0,1,0,1,0,1,0,1] → Raw Score: 4
Frequently asked questions
Is Vcity an official operator?
No. This guide is independent. The identity of Vcity is unverified except for individually reviewed primary-source facts. The demo does not certify or reproduce any outside product.
How does the wallet restoration work?
You can manually restore the balance to 1000 if you are idle and your balance is below 10. This preserves fractional carry. It is not an automatic replenishment.
What happens if I reload the page during a draw?
Reloading ends an unfinished draw without refund or resume. The balance persists locally, but the current round is not saved.
