Who can explain what this BitmapPunks, which has raised the current Ethereum network Gas fee to about 54 gwei, is all about?

Etherscan data shows that the current Ethereum network Gas fee has risen to about 54 gwei.

Earlier today, Slow Fog's Yu Xian posted on X stating: "The BitmapPunks that are raising Ethereum Gas

is indeed a fully-onchain, ultra-large, hybrid collection, as shown in the picture. However, the contract is not open-source verified, and I haven't looked closely to see if there are any risks." $ETH