🔐 PvP Battle Legitimacy Check

"The future grows from the seeds of the past."

A deterministic provably-fair verification script for validating the result of a PvP battle based on player bets and a cryptographic seed.

The script allows anyone to independently verify that a battle result was not manipulated by checking:

• the integrity of the seed
• the correctness of the winner selection algorithm

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📦 Project Files

.
├── pvp_battle_legit_check.py   # Verification script
├── test_roll.json              # Example battle data
└── README.md

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⚙️ How It Works

The verification process consists of two main steps.

1️⃣ Seed Hash Verification

Before the battle begins, the system publishes the SHA256 hash of a secret seed.

Later the seed is revealed.

The script checks that the revealed seed matches the previously published hash:

SHA256(seed_bytes) == provided_hash

If the hash does not match, the round is invalid.

This prevents the seed from being changed after bets are known.

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2️⃣ Weighted Winner Determination

Each player's bet increases their probability of winning.

To avoid floating-point inaccuracies, bets are converted into atoms.

ATOM = 0.01

Example:

Bet	Atoms
20.00	2000
10.00	1000

Total atoms:

3000

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Random Index Generation

The seed is converted into a large integer:

rand_int = int.from_bytes(seed_bytes, "big")

Then a deterministic index is calculated:

index = rand_int % total_atoms

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Winner Selection

Each player occupies a range proportional to their bet.

Example:

Player	Bet	Atom Range
Player A	20	0–1999
Player B	10	2000–2999

If the generated index falls within a player's range — that player wins.

Because the algorithm is deterministic, anyone running the script will get the same result.

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📂 Example Roll Data

File: test_roll.json

[
  {
    "amount": 20,
    "id": 409,
    "username": "@Mityaich89"
  },
  {
    "amount": 10,
    "id": 410,
    "username": "@Maks77"
  }
]

---

🔑 Example Verification Data

Seed:

64c5a63257ad213f2ec6e2b12650f50b1b07d47fa291f8f51b93bc4a1fdc8ae3

Published hash:

de2f547e08e7647d7b3335cc4e7450e2082a054e13057662c41543838b326b2b

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🚀 Usage

Run the script from the command line:

python pvp_battle_legit_check.py \
--seed 64c5a63257ad213f2ec6e2b12650f50b1b07d47fa291f8f51b93bc4a1fdc8ae3 \
--hash de2f547e08e7647d7b3335cc4e7450e2082a054e13057662c41543838b326b2b \
--json test_roll.json

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✅ Example Output

Hash verification passed! ✓

┌──────────────────────────┐
│ Winner ID: 409           │
│ Username: @Mityaich89    │
│ Amount: 20               │
└──────────────────────────┘

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🔎 Why This Is Provably Fair

The system follows a commit-reveal cryptographic scheme.

Step 1 — Commit

The system generates a random seed and publishes its hash:

SHA256(seed)

Example:

de2f547e08e7647d7b3335cc4e7450e2082a054e13057662c41543838b326b2b

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Step 2 — Betting

Players place bets while only the hash is known.

The actual seed remains secret.

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Step 3 — Reveal

After betting ends, the seed is revealed.

Anyone can verify:

• the seed matches the published hash
• the winner was determined fairly

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🛡 Deterministic Guarantees

Given the same:

• seed
• hash
• bet data

The script will always produce the same winner.

This makes the system:

• transparent
• reproducible
• tamper-resistant

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🧰 Requirements

Python 3.8+

Standard library only:

decimal
hashlib
json
argparse
os

No external dependencies required.

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📜 License

MIT License