This did not go over so well for the people who were eager to get a spot in line to mint NFTs that cost 2.5 ETH ($7,650), but was selling with a floor price of 13.1 ETH ($40,000) on the secondary market shortly after the mint completed. If the person behind the Sybil scheme flipped their NFTs for the current floor price, they could make upwards of $1.6 million in profit.
The NFT project "Moonbirds" generated so much hype that they implemented a raffle system for the many people who hoped to get on the project's allowlist, hoping to make it more fair. However, because it is relatively trivial for a person to create many crypto wallets, a person was able to game the system by creating over 400 wallets, which went on to win more than 50 slots on the project allowlist. This strategy — creating many accounts or wallets to gain an advantage — is known as a "Sybil attack".