The project blamed the theft on a previous contractor who had the private key. They also explained that the attacker seemed to be a developer based on the fact that they had "specialized knowledge of ZERO's internal security systems".
Wilder World game suffers $1.8 million theft, blames contractor
Wilder World is a blockchain-based racing game that uses all the buzzwords: blockchains, artificial intelligence, and metaverse. On March 16, someone with access to the project deployer's private key upgraded legacy contracts and transfer the project's $WILD and $MEOW tokens to themselves. Altogether, the attacker profited 515 ETH (~$1.8 million), which they then laundered through the Tornado Cash cryptocurrency tumbler.