There is a BETA ROM which is found all over the net that has that level which you can play. You can't finish the level because it wasn't complete, and it's slightly different from that one in the video. Apparantly the BETA cart was stolen during a press release and copies were released around market places. Their angle of course, was to entice customers by providing a game that wasn't released yet. Sonic 2 is one of the most interesting games as far as edits go, because a lot of stuff was cut.
