From Halopedia, the Halo wiki
Hi there, I'm new to the wikis, but I love Halo, and more than anything its imagery, so I been recreating a couple covers, you know if I can colab them here?
The portfolio so you can know what I am talking about: https://www.artstation.com/artwork/k4dKn2
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Fair Use has a limited application than what the public would think is considered fair. In this case, it is to avoid depriving the parties (i.e. publishers) from reaping the fruits of their (whether contractual or not) partnership with the primary party (in this case, Microsoft/343i).
"Publicly accessible" wouldn't mean having it hosted in this wiki as being "fair use". With that said, if there are preview pages in the publisher's website, leave it as it is and just add in the link in the product article's "External link" section (or create a section if it's not there).
There's a reason why the wiki does not upload the seven preview pages of Halo: Initiation from Dark Horse Comics' website. Because it is not fair use. ;)