On Reddit the author states: "I do not consent to my name or drawings appearing in a pack created by artificial intelligence." So it is not "free" and the author will likely come petty harassing you with DMCA if they dislike you or your project. Be careful!
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I didn't harass you. I just uploaded it so that someone who needs it can use it in their games for free. I don't want an old drawing I made to be recreated by AI and sold as an asset pack with my name on it. As you can see in the tags, I wrote "No-AI". Please don't take it personally, I have no problem with you.
I think you’re getting a few things mixed up. Free doesn’t automatically mean public domain. It just means it doesn’t cost money but the creator still owns it and gets to decide how it can be used and what license applies. If you’re looking for assets to modify you should look for projects with a license that specifically allows for it. I also haven’t seen anybody harassing you. You asked if you could modify and redistribute their assets and they said no.