function rngComplete(
    uint256 _randomNumber,
    uint256 _rngCompletedAt,
    address _rewardRecipient, // @audit can set any address
    uint32 _sequenceId,
    AuctionResult calldata _rngAuctionResult
) external returns (bytes32) {
    // @audit should only be callable by rngAuctionRelayer
    if (_sequenceHasCompleted(_sequenceId)) revert SequenceAlreadyCompleted();
    uint64 _auctionElapsedSeconds = uint64(
        block.timestamp < _rngCompletedAt ? 0 : block.timestamp - _rngCompletedAt
    );
    if (_auctionElapsedSeconds > (_auctionDurationSeconds - 1)) revert AuctionExpired();
    // Calculate the reward fraction and set the draw auction results
    UD2x18 rewardFraction = _fractionalReward(_auctionElapsedSeconds);
    _auctionResults.rewardFraction = rewardFraction;
    _auctionResults.recipient = _rewardRecipient;
    _lastSequenceId = _sequenceId;

    AuctionResult[] memory auctionResults = new AuctionResult[](2);
    auctionResults[0] = _rngAuctionResult;
    auctionResults[1] = AuctionResult({
        rewardFraction: rewardFraction,
        recipient: _rewardRecipient
    });

    uint32 drawId = prizePool.closeDraw(_randomNumber);

    uint256 futureReserve = prizePool.reserve() + prizePool.reserveForOpenDraw();
    uint256[] memory _rewards = RewardLib.rewards(auctionResults, futureReserve);

    emit RngSequenceCompleted(
        _sequenceId,
        drawId,
        _rewardRecipient,
        _auctionElapsedSeconds,
        rewardFraction
    );

    for (uint8 i = 0; i < _rewards.length; i++) {
        uint104 _reward = uint104(_rewards[i]); 
        if (_reward > 0) {
            prizePool.withdrawReserve(auctionResults[i].recipient, _reward);
            emit AuctionRewardDistributed(_sequenceId, auctionResults[i].recipient, i, _reward);
        }
    }

    return bytes32(uint(drawId));
}
function rngComplete(
    uint256 _randomNumber,
    uint256 _rngCompletedAt,
    address _rewardRecipient, 
    uint32 _sequenceId,
    AuctionResult calldata _rngAuctionResult
) external returns (bytes32) {
    // @audit only called by rngAuctionRelayer
    if (msg.sender != rngAuctionRelayer) revert NotRelayer();
    ...
}
