Chain id 11155111. NO launch token, NO pool, NO distributor: application contracts only. The contract holds real user funds, so every rule below is a hard requirement. Do not claim an audit was performed.

GAME. A play costs a buy of IMDO plus a 1 USDC entry. One play per address per UTC day. The whole 1 USDC goes into ONE running pot. Every play gets one verifiable random roll and wins with probability 1 in ODDS (default 2500, an immutable constructor argument, minimum 2). On a win the ENTIRE pot is split 50/50: half to the winner, half to an immutable offsetsRecipient; any odd unit goes to offsetsRecipient; the pot resets to zero. There is no daily payout; the pot only grows until someone wins.

play(uint256 minTokensOut) external payable nonReentrant:

1. Revert if the caller already played in the current UTC day (day = block.timestamp / 1 days).
2. Chainlink VRF v2.5 DIRECT FUNDING, native payment: read the VRF wrapper's calculateRequestPriceNative for the callback gas limit; that fee is taken from msg.value; the remainder is swapEth.
3. Require swapEth to be worth at least MIN_SWAP_USD (default 5 USD, immutable) using a Chainlink ETH/USD AggregatorV3 feed (immutable address). Reject a stale (older than 1 hour), zero or negative answer. Allow 2% tolerance below the minimum.
4. Swap swapEth for the game token with the Uniswap v4 PoolManager (unlock/swap/settle/take, native ETH in) through the configured pool key, delivering the tokens straight to msg.sender. Revert if tokens received < minTokensOut. Measure the output by the recipient's balance change, never by a return value alone. The swap is a BUY only.
5. Pull exactly ENTRY_USDC (1,000,000 units of a 6-decimals USDC, immutable) from msg.sender with transferFrom (the caller approves first) and add it to pot.
6. Request one random word and store requestId => player. Emit Played(player, requestId, day, swapEth, tokensOut).

fulfillRandomWords(requestId, words): callable ONLY by the VRF wrapper (rawFulfillRandomWords pattern). It must NEVER revert. If words[0] % ODDS == 0: prize = pot / 2; offsets = pot - prize; pot = 0; credit prize to the player and offsets to offsetsRecipient by trying a USDC transfer in a try/catch and, if that transfer fails, recording the amount in claimable[address] so a blacklisted or reverting recipient cannot block the callback. Provide claim() for anyone to withdraw their own claimable balance. Emit Settled(requestId, player, won, prize, offsets). A requestId settles at most once. Out-of-order and concurrent fulfillments must each be evaluated against the pot at that moment.

CONFIG (the ONLY mutable thing): the game token and its v4 pool key (currency0 native ETH, currency1 token, fee, tickSpacing, hooks) may be changed by an owner (a Safe multisig, set in the constructor) through a TIMELOCK: proposeConfig(...) starts a delay of CONFIG_DELAY (default 48 hours, immutable), applyConfig() executes only after the delay, cancelConfig() cancels. Emit events for each. While a proposal is pending, play() keeps using the old config. The owner can do NOTHING else: no pause, no withdraw, no change to the pot, the odds, the entry fee, the minimum, the 50/50 split, offsetsRecipient, USDC, the price feed or the VRF settings, and cannot move user funds or the pot. Say exactly what the owner can call in the README. Immutable constructor arguments: usdc, offsetsRecipient, vrfWrapper, ethUsdFeed, poolManager, odds, minSwapUsd, entryUsdc, configDelay, owner, and the initial token and pool key.

SAFETY. Reentrancy-guard every external entry point; follow checks-effects-interactions; no ERC-777 or fee-on-transfer assumptions for USDC; handle USDC 6 decimals and the ETH/USD feed decimals correctly; use safe-transfer patterns; no unchecked arithmetic on money. The contract must never hold ETH beyond a transaction (refund any excess msg.value after the swap and the VRF fee).

BUILD REPRODUCIBILITY: the repository MUST contain a root foundry.toml setting bytecode_hash = "none" under [profile.default]; pin solc, optimizer runs and evm_version. The README must quote foundry.toml verbatim and list every constant and who can call what.

TESTS (Foundry; a different worker writes them). Use mocks for the VRF wrapper, the ETH/USD feed, the PoolManager swap and USDC. Cover: one play per address per UTC day and the rollover at 00:00 UTC; the whole 1 USDC enters the pot; the exact 50/50 split with an odd-unit pot; the pot resets to zero after a win; forced words that do and do not win at ODDS; only the VRF wrapper can fulfill; fulfillment never reverts even when a recipient reverts or is blacklisted (claimable fallback); a request settles once; concurrent pending plays settle against the pot at fulfillment; stale, zero and low-value price feeds are rejected; the 2% tolerance boundary; minTokensOut slippage; excess msg.value refunded and no ETH left in the contract; reentrancy attempts via a malicious token and a malicious recipient; the timelock (apply before the delay reverts, cancel works, old config stays live while pending); the owner cannot move funds or touch any immutable; a fuzz/invariant test that pot plus claimable plus paid out equals USDC received. Keep the contract small and readable.