Rock Paper Scissors game on Neo X demonstrates anti-MEV protection

Neo Global Development has launched a “Rock Paper Scissors” game on the Neo X sidechain that lets users experience Neo’s anti-MEV features firsthand. The game is live and playable at rps.ngd.network.

MEV refers to the profit that block producers and bots can capture by reordering, inserting, or front-running transactions within a block, often at the expense of standard users. Front-running occurs when a bot watches the mempool, the public waiting area where pending transactions sit before they are confirmed, spots a profitable move, and rushes in a competing transaction with a higher fee to capture the gain first.

How the game works

Players connect a wallet through one of three options: MetaMask, Neon Wallet, or WalletConnect. Participants need at least 0.1 $GAS on Neo X to cover the required transactions.

The game offers two modes, and the difference between them is the lesson. Standard Mode advertises a 10x payout, while MEV-Protected Mode pays 2x.

The larger Standard Mode reward is not simply the better deal. In Standard Mode, a player’s move is submitted through the public mempool, where a front-running bot can observe it and copy it in time to claim the prize, so the headline payout is exposed to capture.

In MEV-Protected Mode, the move remains hidden until the result is finalized, preventing front-running and allowing the player to keep smaller but reliable winnings.

NGD encourages players to try both modes with a small amount of $GAS to see the contrast for themselves, and the game explains why each round was won or lost and how MEV factored into the outcome.

All $GAS that accumulates in the game, including rewards won by bots and rewards won by the house, returns to the pool so players can keep testing. NGD has said it will continue replenishing the pool if necessary.

The protection underneath

Neo X eliminates toxic MEV at the protocol level using dBFT consensus and enveloped transactions. dBFT is the consensus mechanism Neo uses to finalize blocks. Enveloped transactions are kept encrypted and hidden until they are finalized and ordered inside a block, so no validator, block producer, or MEV searcher can view or exploit a transaction in advance.

In the game, this is why a player’s move cannot be seen until the round is settled. As NGD frames it, “No one can peek, no one can front-run. Win or lose, the game is fair.”

Neo X’s anti-MEV system went live through the v0.4.2 upgrade in September 2025. The mechanism relies on distributed key generation and threshold decryption, which requires a two-thirds quorum of consensus nodes to decrypt transactions only after their ordering is finalized. The Rock Paper Scissors game demonstrates that already-shipped protection rather than a new piece of infrastructure.

The game’s code is fully open source, hosted in COZ’s GitHub repository.

The full announcement can be found at the link below:
https://x.com/ngd_neo/status/2066793344261365884