Hello cobmin, I'm sorry, but I cannot permit its use or sale in an NFT game as it conflicts with my license. In this case, I would suggest commissioning some sprites for which you can obtain full copyrights.
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I will not be selling your assets. Not even as NFTs. The game is free to play, and I would use your assets as NPCs and dungeons. Cob's Farm - Adventure Game with Farming and Combat (cobsfarm.com)