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+# QDuel Contract Proposal
+
+## Overview
+
+QDuel is a duel contract with reusable player balances. A room owner posts a
+stake, another player matches it, and the winner receives the pooled amount
+minus fees. Owners can keep a deposit on the contract to auto-open a new room
+after each duel or timeout.
+
+## Motivation and Goals
+- Keep duels lightweight with bounded storage.
+- Provide deterministic, verifiable winner selection.
+- Allow optional rematching with configurable stake growth.
+- Refund or recycle funds when rooms expire.
+- Let the team adjust fees and TTL without redeploying.
+
+## Contract Summary
+The contract maintains up to 512 active rooms. Each room stores:
+roomId, owner, allowedPlayer (optional), amount, closeTimer, and lastUpdate.
+A separate users map tracks the room owner profile:
+roomId, depositedAmount, locked, stake, raiseStep, and maxStake.
+
+## Key Parameters and Defaults
+- minimumDuelAmount = 10,000 QU
+- ttlHours = 3
+- fee scale = 1000 (1.00% = 10 bps)
+- devFeePercentBps = 15 (0.15%)
+- burnFeePercentBps = 30 (0.30%)
+- shareholdersFeePercentBps = 55 (0.55%)
+- asset for shareholders distribution: Random Lottery (RL, assetName 19538)
+- tick maintenance period: every 100 ticks
+
+## Room Creation
+CreateRoom(owner, allowedPlayer, stake, raiseStep, maxStake):
+- invocationReward must be >= minimumDuelAmount and >= stake.
+- stake is locked in the room; any extra sent becomes depositedAmount.
+- each owner can have only one active room.
+- roomId is derived from tick and invocator data; collisions are retried.
+
+## Room Join and Settlement
+ConnectToRoom(roomId):
+- joining player must send at least room.amount; excess is refunded.
+- winner = K12(prevSpectrumDigest XOR player ids XOR tick), LSB picks min/max id.
+- if winner derivation fails, both stakes are refunded and the room is closed.
+- otherwise, the pooled amount is split into:
+  - devFee -> teamAddress
+  - burnFee -> burned
+  - shareholdersFee -> RL holders (remainder burned)
+  - winner -> winner payout
+
+## Fees and Shareholders Distribution
+
+Fee percentages are set in basis points over the scale 1000. The shareholder
+portion is rounded down to a value that can be evenly distributed per share.
+Distribution uses dividendPerShare = shareholdersFee / NUMBER_OF_COMPUTORS.
+Each RL holder receives shares * dividendPerShare, and any remainder is burned.
+
+## Example Duel Settlement (default fees)
+- Room amount: 100,000 QU from player1 and 100,000 QU from player2.
+- Total pot: 200,000 QU.
+- Fees:
+  - devFee: 200,000 * 0.15% = 300 QU
+  - burnFee: 200,000 * 0.30% = 600 QU
+  - shareholdersFee: 200,000 * 0.55% = 1,100 QU (rounded down if needed)
+- Winner payout: 200,000 - (300 + 600 + 1,100) = 198,000 QU.
+
+## Auto-Requeue and Deposits
+Room owners can keep a deposit on the contract:
+- Deposit adds to depositedAmount.
+- Withdraw removes free depositedAmount (not locked stakes).
+- After a duel, only depositedAmount is considered for auto-requeue.
+- After a timeout, depositedAmount + locked stake are considered.
+
+## Next stake is computed as:
+- If raiseStep > 1, nextStake = stake * raiseStep.
+- nextStake is capped by maxStake if provided.
+- If nextStake < minimumDuelAmount, funds are returned and the user profile
+  is removed.
+- If room creation fails, all available funds are returned and the user profile
+  is removed.
+
+## Lifecycle Management
+- BEGIN_EPOCH locks the contract until the default RL init time is reached.
+- END_TICK runs every 100 ticks to decrement room timers and finalize expired
+  rooms.
+- Room timers use lastUpdate to avoid large gaps across epochs.
+
+## Admin Controls
+- SetPercentFees: teamAddress only; total fee must be < 100%.
+- SetTTLHours: teamAddress only; ttlHours must be > 0.
+- GetPercentFees, GetTTLHours, GetRooms, GetUserProfile are public queries.
+
+## Limitations and Risks
+- Deterministic randomness can be influenced by entities affecting the previous
+  spectrum digest; the digest is external to this contract.
+- Only room owners are tracked; joiners have no stored profile.
+- Auto-requeue depends on available deposits and minimumDuelAmount.
+- Fee misconfiguration can shrink winner payouts.
+
+## Conclusion
+QDuel provides a compact duel system with adjustable fees, configurable room
+TTL, and optional auto-requeue mechanics based on owner deposits. The design
+keeps state bounded while supporting repeat play without redeploys.
+
+# Available Options
+> Option 0: no, dont allow
+
+> Option 1: yes, allow
+
+# Code
+[PR](https://github.com/qubic/core/pull/705)