An AVGN Nazi is a hater who specifically targets video game reviewers on YouTube. These specific haters believe that anyone who reviews games who is not the Angry Video Game Nerd is a ripoff of said reviewer. These haters flame the reviewer with hostile and/or bigoted comments, flag videos with the purpose of getting them removed, or attempt to get accounts banned.
(insert username here), don't let those AVGN Nazis get to you. If you quit YouTube, they win.