Flilix on 21 October 2017
I don't think I've even played a game below 65 metascore. The lowest was Mario & Sonic at the London 2012 Olympic Games (66 meta), which was pretty good imo.
I also want to mention Mini Race by Gamedesign. It's the best racing game of all time. However, I doubt it would get a 65 on metascore, since reviewers wouldn't be able to appreciate this piece of art.
http://gamedesign.jp/flash/race/race.html
