Account was made today, 4 hours later post this game has a virus, X to doubt you really did ANY research and just are believing a likely false positive.
Vikingfile seems to do the same thing that several other Ad supported download services do. When you click the Download button, it opens a new tab which is actually an Advertisement, but it appears to be a legit download page/link.
My guess is that the other poster fell for the 'official looking' download, clicked the fake link, and the Ad happily offered to install various and sundry Malware on his machine.
Vikingfile worked fine for me, BUT, it did throw an 'official download link' advertisement in a new tab. It is easy to close that new tab and click the download link again, but not everyone is savvy enough to realize the difference between a 'pop up ad' and an actual download link.