Maniacal
the green Napoleon
Apparently there was an ARG in the Steam sale somehow, people finally figured it out.
https://www.reddit.com/r/pcmasterrace/comments/3yyunv/steam_secret_badge_solved_check_comments/
http://store.steampowered.com/app/253750
Basically log into the Steam store in your web browser (to the page for Ikaruga), type "search" (just into the page, nowhere specific), press enter and enter the code "1v7531" to get a Red Herring steam profile badge worth 100XP.
Possibly more to this that hasn't been found yet.
https://www.reddit.com/r/pcmasterrace/comments/3yyunv/steam_secret_badge_solved_check_comments/
http://store.steampowered.com/app/253750
Basically log into the Steam store in your web browser (to the page for Ikaruga), type "search" (just into the page, nowhere specific), press enter and enter the code "1v7531" to get a Red Herring steam profile badge worth 100XP.
Possibly more to this that hasn't been found yet.