Only because you said, 'I don't know what to do', I thought I'd add my 2 cents to the conversation.



Way back in the day HASBRO were pretty cool when they came out and said that unofficial merchandising of the MLP franchise would be allowed. There were limits I'm sure, but people would not be pursued for selling their work ( IE their work would be owned by them even thought the franchise is licensed). If you were able to find these official press releases and the HASBRO policies that support them, maybe you would have rights to sue over HASBRO. But given the image is already freely available in the public domain, I'd agree it is an unusual precedence, this is where a US solicitor would come into the conversation. Their only line would be if CNN profited ( which maybe I guess ) from the use of your work. Could you imagine if a humble artist from dA became embroiled in one of the biggest fair use and ownership litigation.