In endGame() function the transfer used for Ether payouts in the contract is prone to failure due to its 2300-gas stipend limit.
The contract uses transfer to send Ether to the player upon winning. This imposes a 2300-gas stipend, which may fail if the recipient is a contract with a fallback function consuming more gas.
The Solidity best pracise is to use call for transferring Ether, as it provides greater flexibility by forwarding all available gas to the recipient.
If transfer fails, the Ether payout will not occur, locking funds in the contract and potentially leading to player dissatisfaction.
Manual Review
Aderyn
Replace transfer with call for Ether transfers:
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