Instead of being abruptly told that this guy's clinically insane, there should have been hints at the later levels that something is not right. The level with the death and the last levels in particular struck a chord with me, though.
Comment correcting grammar and/or spelling of other comment written, and insulting intelligence of writer of said comment in an attempt to compensate for user's own insecurities. Usually written without proper grammar.
Comment praising game or saying the game is retarded, written by a retard. Declaratory statement informing readers to whether the user has rated -666677579/5 or God/5.